# Math Homework Help

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### Showing All Questions Unanswered Answered Popular Recommended in Math

• Math
Let the length of the pen be L and the width be W. One of the sides of the pen will be the barn. As we have to maximise the area of the pen that is constructed, the barn should form one of the...

Asked by ib1995 on via web

• Math
We know that the surface area of a sphere is given by the formula S=4*pi*r^2, where r is the radius of the sphere. We need the rate of change of the surface area with respect to the radius when the...

Asked by paul1234 on via web

• Math
The identity that has to be proved is : (tan x + 1)/(tan x) - (sec x * csc x + 1)/(tan x + 1) = (cos x)/(sin x + cos x). We know that tan x = sin x / cos x , sec x = 1/cos x and csc x = 1/sin x....

Asked by jimsteven on via web

• Math
First, let us find the surface area that has to be wrapped. That is the surface area of the cylinder given as 2*pi*r*h => 2*pi*(49/2)*18 When the wire is being wrapped on this surface area, the...

Asked by kanug on via web

• Math
Your question is quite vague. I assume you need to find f(x) which is a linear function. Let f(x) = ax + b 2*f(1-2x) + 3*f(x) = -2x + 14 => 2*[a( 1 - 2x) + b] + 3(ax + b) = -2x + 14 => 2a -...

Asked by iuhih on via web

• Math
We have to find the sum of the first 10 terms of the series 4,10,28,82,244... Looking at the series it is not an arithmetic sequence or a geometric sequence. But if we subtract 1 from each term 4 -...

Asked by dhopkins895 on via web

• Math
We have the curves x = t^2 and y = 3t^2 - t. We have to find the second derivative of y with respect to x. y = 3t^2 - t => y = 3*x - x^(1/2) => dy/dx = 3 - (1/2)*x^(-1/2) d^2y/dx^2 = 0 -...

Asked by callen202 on via web

• Math
The slope of a curve y = f(x) at the point (x, y), where y is the dependent variable and x the independent variable is given as the value of the derivative of y with respect to x. We have (y/x -...

Asked by schoolier on via web

• Math
The logarithm function is defined such that log(a) b = c, implies b = c^a. Here a is called the base of the logarithm. If we have the notation merely as log without a base specified it denotes the...

Asked by rbeaker91 on via web

• Math
We have to solve the following system of equations: 2x - z = 5...(1) x + 2y = 7...(2) x + y + z = 2 ...(3) (1) gives 2x - z = 5 => z = 2x - 5 (2) gives x + 2y = 7 => y = (7 - x)/2 Substitute...

Asked by timw996 on via web

• Math
We have to find the solution of sqrt(3m - 2) + 2 = m sqrt(3m - 2) + 2 = m subtract 2 from both the sides => sqrt(3m - 2) = m - 2 square both the sides => 3m - 2 = (m - 2)^2 => 3m - 2 = m^2...

Asked by schooldump on via web

• Math
The plane P1: x + y + 3z = 2 intersects the plane P2: x - y + 2z = 0 in a line. Determine the cross products of the normal vectors of the two planes P1 and P2. < 1 1 3 > X < 1 -1 2 > is...

Asked by rosemin on via web

• Math
The scalar equation of a plane is a function of a vector in a plane and its normal vector. no one vector can fully describe a plane, but the scalar equation of a plane always fully describes its...

Asked by rosemin on via web

• Math
The definition of the word scalar, a real number associated to an appropriate unit of measure. Vectors are the convenient to use in determining the equation of a line in space....think of it as...

Asked by rosemin on via web

• Math
We have to solve the equation : (3x + 1)/4 = (4x - 1)/8 + 2 (3x + 1)/4 = (4x - 1)/8 + 2 Let's make the denominators of all the terms the same. => 2*(3x + 1)/8 = (4x - 1)/8 + 16/8 => 6x + 2 =...

Asked by xetabeta on via web

• Math
You need to write the factored form of the number 595 such that: `595 = 1*5*119` Hence, the divisors of 595 are `{1;5;119;595}` You need to write the factored form of the number 252 such that:...

Asked by mallocio on via web

• Math
We need to find lim x-->0 [(sqrt(x+5) - sqrt(5 - x))/3x]. If we substitute x = 0 in the given expression we get the indeterminate form 0/0. We can use l'Hopital's rule here and substitute the...

Asked by xetaalpha2 on via web

• Math
We need to find the solution for x^3 + 5x^2 -x - 5 < 0. x^3 + 5x^2 -x - 5 < 0 => x^2( x + 5) - 1(x + 5) < 0 => (x^2 - 1)(x + 5) < 0 => (x - 1)(x + 1)(x + 5) < 0 For the...

Asked by thomas666 on via web

• Math
We have the function f(x) = x/(x - 1)^2 and we have to find the first and the second derivatives. f(x) = x/(x - 1)^2 => f(x) = x*(x - 1)^-2 Use the product rule to calculate the first...

Asked by xetaalpha on via web

• Math
We have to find the minimum g(t)=t^3-25t+6 on the interval [-2.5, 5]. First, we find the derivative of g(t). That is equated to 0 to solve for x. The value of the second derivative is positive...

Asked by tafy222 on via web

• Math
There can be infinite number of planes that intersect the planes P1: x + y + 3z - 2 = 0 and P2: x - y + 2z = 0. The required plane should not be parallel to x + y + 3z = 2 or the vector < 1, 1,...

Asked by rosemin on via web

• Math
We need to find x and y from 3x - ix - 2y = 12 - iy - i 3x - ix - 2y = 12 - iy - i => 3x - 2y - ix = 12 - i(y + 1) equate the real and the complex coefficients. 3x - 2y = 12 x = y + 1 substitute...

Asked by ymeri001 on via web

• Math
The man buys a dozen or 12 cameras for \$1800. They are sold at a profit of \$36 each. The initial cost of each camera is \$1800/12 = \$150. The profit made for the investment of \$150 in buying a...

Asked by helpme2244 on via web

• Math
We have to solve: sqrt(1 - sqrt (x^4 - x)) = x - 1 sqrt(1 - sqrt (x^4 - x)) = x - 1 square both the sides => (1 - sqrt (x^4 - x)) = (x - 1)^2 => (1 - sqrt (x^4 - x)) = (x^2 + 1 - 2x) =>...

Asked by potziunea on via web

• Math
The area of a trapezium with parallel sides of length a and b which are separated by a distance d is given by (1/2)*(a + b)*d. Here, we have a trapezium with parallel sides of length 6 and 30 and...

Asked by ib1995 on via web

• Math
You need to find the expression for the area of the square inscribed in a circle in terms of the radius of the circle given as r. A square inscribed in a circle is one that has the largest sides...

Asked by b198125 on via web

• Math
This is a quadratic equation of the form: ax^2 + bx + c = 0. There are two roots or zeroes of the equation given by the formula: x1 = [-b + sqrt (b^2 - 4ac)]/2a and x2 = [-b - sqrt (b^2 - 4ac)]/2a...

Asked by janel199026 on via web

• Math
If the first term of an AP is a and the common difference is d, the sum of the first n terms is (a + a + (n - 1)*d)*n/2 The sum of the first 30 terms is (a + a + 29d)*(30/2) => (2a + 29d)*15 =...

Asked by callen202 on via web

• Math
The length of the ramp is dependent on the angle that it forms with the horizontal. Let us denote the angle at which the ramp is inclined to the ground to be A, and the length of the inclined...

Asked by hala718 on via web

• Math
The student council originally sold tickets at \$11 and the number of people who attended was 400. The total revenue with a ticket price of \$11 was 400*11 = \$4400. According to their estimates, a \$1...

Asked by superzack411 on via web

• Math
In the problem the ring that is threaded in the string has a mass of 0.1 kg. The string is attached at the ends A and B with the bead hanging in the middle at point R The tension is the same...

Asked by littlecrumpet on via web

• Math
We have to solve 2x^4 - 11x^3 + 23x^2 - 19x + 5 = 0 2x^4 - 11x^3 + 23x^2 - 19x + 5 = 0 => 2x^4 - 3x^3 - 8x^3 + 12x^2 + 10x^2 + x^2 - 15x - 4x + 5 = 0 => 2x^4 - 3x^3 + x^2 - 8x^3+ 12x^2 - 4x +...

Asked by tessenotes on via web

• Math
To calculate the total amount including the principle and the interest that \$6000, deposited at an annual rate of interest of 6% compounded semi-annually, becomes after 3 years, we use the...

Asked by xetaalpha on via web

• Math
As the integers we have to find are consecutive, we can equate a = x, b = x + 1, c = x +2 , d = x + 3 and e = x + 4. x^2 + (x + 1)^2 + (x + 2)^2 = (x + 3)^2 + (x + 4)^2 => x^2 + (x + 1)^2 –...

Asked by thomas666 on via web

• Math
We need to find the result of the sum 3^102 + 9*3^100 + 3^103/3. 3^102+9*3^100+3^103/3 => 3^102 + 3^(100+2) + 3^(103 - 1) => 3^102 + 3^(102) + 3^(102) => 3* 3^102 => 3^(102 + 1) =>...

Asked by jolenta on via web

• Math
We need the value of k for which -x+k=2x-1 and 2x+4=4(x-2) have the same solution. 2x + 4 = 4(x - 2) => 2x + 4 = 4x - 8 => 2x = 12 => x = 6 Substitute x = 6 in -x + k = 2x - 1 => -6 + k...

Asked by l0l1 on via web

• Math
We have to find t for (e^t-e^-t)/2=3 (e^t-e^-t)/2=3 => (e^t-e^-t) = 3*2 let e^t = y => y - 1/y = 6 => y^2 - 1 = 6y => y^2 - 6y - 1 = 0 y1 = 3 + sqrt 40 / 2 => 3 + sqrt 10 y2 = 3 -...

Asked by clockbeige on via web

• Math
We have to find the inverse function of f(x) = sqrt(x - 4) + 3. Let y = f(x) y = sqrt(x - 4) + 3 => y - 3 = sqrt(x - 4) square both the sides => (y - 3)^2 = (x - 4) => (y - 3)^2 + 4 = x...

Asked by eligia on via web

• Math
This is a fairly elementary question posed by you and the answer is one that you should be able to derive on your own. I have provided the same for your convenience. 5 cups of water are to be used...

Asked by cindymd on via web

• Math
The wheel makes 1 7/20 rotations in one minute. That is equal to 1 + 7/20 => (20 + 7)/20 => 27/20 rotations in a minute. If it rotates for 48 minutes the number of times it rotates is...

Asked by aqueen84 on via web

• Math
[I can answer only one of your questions, so I'll simplify 5x/(x^2-9) + 4/(2x-6), you can use the same steps for the other.] 5x/( x^2-9) + 4/(2x - 6) change x^2 - 9 to (x - 3)(x + 3) => 5x/(x -...

Asked by rcxx2 on via web

• Math
We have the vertex of the parabola as (2, -3) and the directrix is y = -7. The distance of the vertex from the directrix is -3 - (-7) = 4. This is equal to a. The equation of a parabola with...

Asked by clock-time on via web

• Math
The parabola of which we have to find the equation has a vertex at (-2,3) and a focus at (-4,3). The equation of the parabola is of the form (y - y0)^2 = 4a(x - x0), where(x0, y0) is the vertex and...

Asked by eng-bryan on via web

• Math
I have changed the question as you have said that the sum has to be found and an equation to be solved. (2 - 3x)/(x^2 - 9) = 4/(2x - 6) => (2 - 3x)/(x - 3)(x + 3) = 4/2*(x - 3) => (2 - 3x)/(x...

Asked by boscow on via web

• Math
The cylindrical hot tub is being emptied at a rate 5 ft^3 / 2 minutes or (5/2) ft^3 per minute. The height of the tub is 4 feet and the radius of the tub is 3 feet. For a cylinder with a height h...

Asked by ifrab on via web

• Math
We have two similar cylinders, this means the ratio of their radius is equal to the ratio of their height. The lateral area of the cylinder are 196*pi and 342*pi. The lateral area of a cylinder...

Asked by ib1995 on via web

• Math
For a square inscribed in a circle with radius r, the diagonal of the square is equal to the diameter of the circle. Let the side of the square be s, its diagonal by the Pythagorean Theorem is...

Asked by b198125 on via web

• Math
Measures of central tendency include mean, mode and median among several others. They are important in research to analyze the data has been collected. When a research is conducted, information on...

Asked by aigo on via web

• Math
The vertex of the parabola is (0,0), the axis is the x-axis and it passes through the point (3, -6). As the axis of the parabola is the x-axis it opens sidewards. The general equation of a parabola...

Asked by paul-rider on via web