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The latest questions and answers, from members following Math at eNotes.Thu, 24 Apr 2014 20:51:29 PSTen-us(1) Find the multiplicative inverse of 9 in `ZZ160 ` : This is...
http://www.enotes.com/homework-help/use-euclids-algorithm-find-multiplicative-inverse-468358
(1) Find the multiplicative inverse of 9 in `ZZ160 ` : This is equivalent to finding the multiplicative inverse of 9 modulo 160. We use the extended Euclidean algorithm: (1) 160=9(17)+7(2) 9=7(1)+2(3) 7=2(3)+1(4) 2=1(2)+0 So 1=7-2(3). ==> 1=7-(9-7(1))(3)=7(4)-9(3) ==> 1=(160-9(17))(4)-9(3)=160(4)-9(71) So the multiplicative inverse for 9 modulo 160 is -71, or in the range [0,159] the inverse is 89. ** Check: 9(89)=801=160(5)+1 so the...http://www.enotes.com/homework-help/use-euclids-algorithm-find-multiplicative-inverse-468358Thu, 24 Apr 2014 20:51:29 PSTWe are asked to find the derivative of `g(x)=6x^2e^(-x) ` : Use the...
http://www.enotes.com/homework-help/find-derivative-g-x-6x-2e-x-468445
We are asked to find the derivative of `g(x)=6x^2e^(-x) ` : Use the product rule: `g'(x)=(d/(dx)(6x^2))*e^(-x)+(6x^2)(d/(dx)(e^(-x)))` `=(12x)e^(-x)+(6x^2)(-e^(-x)) ` (Using the derivative of `e^u ` ) ` =e^(-x)(12x-6x^2) `http://www.enotes.com/homework-help/find-derivative-g-x-6x-2e-x-468445Thu, 24 Apr 2014 20:15:22 PSTFind the derivative. g(x) = 6x^2e^-x
http://www.enotes.com/homework-help/find-derivative-g-x-6x-2e-x-468445
Find the derivative. g(x) = 6x^2e^-xhttp://www.enotes.com/homework-help/find-derivative-g-x-6x-2e-x-468445#1April 24, 2014, 7:50 pm PSTProve that `sum_(r=2)^n 2/(r(r^2-1))=1/2-1/(n(n+1)) ` : for `n in NN,...
http://www.enotes.com/homework-help/use-mathematical-induction-prove-that-sigma-sign-n-468438
Prove that `sum_(r=2)^n 2/(r(r^2-1))=1/2-1/(n(n+1)) ` : for `n in NN, n>=2 ` (1) Base case: n=2 ==> `sum_(r=2)^2 2/(r(r^2-1))=2/(2(2^2-1))=2/6=1/3 ` while `1/2-1/(n(n+1))=1/2-1/(2(3))=1/2-1/6=1/3 ` , so the base case is true. (2) Inductive hypothesis: assume that for some `k in NN, k >=2 ` that `sum_(r=2)^k 2/(r(r^2-1))=1/2-1/(k(k+1)) ` (3) We show that ` sum_(r=2)^(k+1) 2/(r(r^2-1))=1/2-1/((k+1)(k+2)) ` `sum_(r=2)^(k+1)...http://www.enotes.com/homework-help/use-mathematical-induction-prove-that-sigma-sign-n-468438Thu, 24 Apr 2014 15:50:28 PSTUse mathematical induction to prove that Sigma sign ('n' is on the top...
http://www.enotes.com/homework-help/use-mathematical-induction-prove-that-sigma-sign-n-468438
Use mathematical induction to prove that Sigma sign ('n' is on the top of it and r=2 is underneath it.) 2 \ r(r^2 - 1) = (1\2) - 1 \ n(n + 1) for n = 2,3,4,........ ` `http://www.enotes.com/homework-help/use-mathematical-induction-prove-that-sigma-sign-n-468438#2April 24, 2014, 2:33 pm PST45 is 93% of what? Write algebraically: 45 = (93/100)x = .93x x =...
http://www.enotes.com/homework-help/45-93-317133
45 is 93% of what? Write algebraically: 45 = (93/100)x = .93x x = 45/.93 x = 48.387....http://www.enotes.com/homework-help/45-93-317133Wed, 23 Apr 2014 22:37:31 PST(1) 3x+y=5 (2) -x+2y=-4 Rewrite both: (1) y = 5 - 3x (2) y = (x -...
http://www.enotes.com/homework-help/solve-by-graphing-1-3x-y-5-x-2y-4-2-2x-y-1-2x-y-5-289340
(1) 3x+y=5 (2) -x+2y=-4 Rewrite both: (1) y = 5 - 3x (2) y = (x - 4)/2 Graph: We can see that they intersect at point (2, -1) which is your solution. http://www.enotes.com/homework-help/solve-by-graphing-1-3x-y-5-x-2y-4-2-2x-y-1-2x-y-5-289340Wed, 23 Apr 2014 22:35:47 PSTStatistics obviously comes to mind: weighted averages, averages, mode,...
http://www.enotes.com/homework-help/what-types-maths-used-football-297597
Statistics obviously comes to mind: weighted averages, averages, mode, median, and range. If you are looking at the motion of the football then Newtonian Mechanics from physics with some basic algebra skills can help you determine velocity, velocity upon impact, the parabolic trajectory, and the amount of force necessary to always score from a certain distance. http://www.enotes.com/homework-help/what-types-maths-used-football-297597Wed, 23 Apr 2014 22:32:48 PSTSome helpful things to keep in mind are: --Isolate the variable you...
http://www.enotes.com/homework-help/can-somebody-give-me-steps-how-go-about-doing-201953
Some helpful things to keep in mind are: --Isolate the variable you are solving for to one side--Try to get rid of addition/subtraction before moving on to multiplication/division--for particularly difficult derivations sometimes squaring both sides of an equation can help you solve for the desired variable. --Don't give up!http://www.enotes.com/homework-help/can-somebody-give-me-steps-how-go-about-doing-201953Wed, 23 Apr 2014 22:29:36 PSTIf y=7.5 when x=0.5, find y when x=-0.3 You can set up proportions: ...
http://www.enotes.com/homework-help/y-7-5-when-x-0-5-find-y-when-x-3-117463
If y=7.5 when x=0.5, find y when x=-0.3 You can set up proportions: `(.5)/(7.5) = (-0.3)/(y)` `.5y = -2.25` `y = -2.25 /.5` `y = -4.5` `` ` `http://www.enotes.com/homework-help/y-7-5-when-x-0-5-find-y-when-x-3-117463Wed, 23 Apr 2014 22:24:38 PSTThe ordered pair (2, 36) is a solution for which equation(s)? x = 2 is a...
http://www.enotes.com/homework-help/ordered-pair-2-36-solution-which-equation-s-115215
The ordered pair (2, 36) is a solution for which equation(s)? x = 2 is a vertical line equation that satisfies this condition. (But its not a function!) y = 36 is a horizontal line equation that satisfies this condition. For linear functions: y - 36 = m(x - 2) for any real m. http://www.enotes.com/homework-help/ordered-pair-2-36-solution-which-equation-s-115215Wed, 23 Apr 2014 22:22:00 PSTDirect variation means y varies directly with x. As y goes up; x goes...
http://www.enotes.com/homework-help/write-an-equation-direct-variation-that-includes-82291
Direct variation means y varies directly with x. As y goes up; x goes up. So y = kx for some unknown k. We can solve for this k using the point given (-3, -14) Plug in x and y: -14 = -3k Solve for k -14/-3 = k Simplify k = 14/3 So the function is: f(x) = (14/3)x http://www.enotes.com/homework-help/write-an-equation-direct-variation-that-includes-82291Wed, 23 Apr 2014 22:16:57 PST4x^2 - 8x + 4 = 0 divide everything out by 4 x^2 - 2x + 1 = 0 Its a...
http://www.enotes.com/homework-help/4x2-8x-4-0-solve-by-factoring-342771
4x^2 - 8x + 4 = 0 divide everything out by 4 x^2 - 2x + 1 = 0 Its a perfect square which equals ( x - 1)^2 Set that equal to 0 and solve. (x - 1)^2 = 0 x - 1 = 0 x = 1http://www.enotes.com/homework-help/4x2-8x-4-0-solve-by-factoring-342771Wed, 23 Apr 2014 18:00:07 PSTc=(ab) / (a+b) Get rid of the fraction: c (a + b) = ab ac + bc = ab...
http://www.enotes.com/homework-help/solve-c-ab-b-275078
c=(ab) / (a+b) Get rid of the fraction: c (a + b) = ab ac + bc = ab Distributive Property ac - ab = -bc Isolating the variable we want to one side a (c - b) = = -bc a = -bc / (c-b)http://www.enotes.com/homework-help/solve-c-ab-b-275078Wed, 23 Apr 2014 17:56:56 PST250% of ? is 50 250% in decimal form is 2.5 Rewrite: 2.5x = 50 x =...
http://www.enotes.com/homework-help/250-50-317142
250% of ? is 50 250% in decimal form is 2.5 Rewrite: 2.5x = 50 x = 50/2.5 x = 20http://www.enotes.com/homework-help/250-50-317142Wed, 23 Apr 2014 17:53:05 PST