Math at eNotes
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The latest questions and answers, from members following Math at eNotes.Sat, 26 Jul 2014 06:02:06 PSTen-usThe derivative of a function f(x) is defined as `lim_(h->0) (f(x+h) -...
http://www.enotes.com/homework-help/use-first-principles-find-derivative-f-x-sec-x-470139
The derivative of a function f(x) is defined as `lim_(h->0) (f(x+h) - f(x))/h` . For f(x) = sec x, the derivative from first principles is: `f'(x) = lim_(h->0)(sec(x+h) - sec x)/h` `= lim_(h->0)(1/(cos(x+h)) - 1/(cos x))/h` `= lim_(h->0) (cos x - cos(x+h))/(cos(x+h)*cos x*h)` ` ` = `lim_(h->0)(cos x - (cos x*cos h - sin x*sin h))/(cos(x+h)*cos x*h)` `= lim_(h->0) (cos x(1 - cos h))/(cos(x+h)*cos x*h) + (sin x*sin...http://www.enotes.com/homework-help/use-first-principles-find-derivative-f-x-sec-x-470139Sat, 26 Jul 2014 06:02:06 PSTUse first principles to find the derivative of f(x) = sec x
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Use first principles to find the derivative of f(x) = sec xhttp://www.enotes.com/homework-help/use-first-principles-find-derivative-f-x-sec-x-470139#1July 26, 2014, 5:09 am PSTIntegers are the numbers on the number line (both positive and negative...
http://www.enotes.com/homework-help/what-ia-integer-469375
Integers are the numbers on the number line (both positive and negative numbers). The positive integers are numbers greater than 0 (1,2,3,4 so on). The negative integers are less than 0 (-1,-2,-3,-4 so on). Integers do not include fractions or decimals 1/2 or 5.5 not integers. http://www.enotes.com/homework-help/what-ia-integer-469375Thu, 24 Jul 2014 23:53:50 PSTI'm assuming by "twice the number x" that this refers to the numerical...
http://www.enotes.com/homework-help/twice-number-x-470096
I'm assuming by "twice the number x" that this refers to the numerical equation 2x. When a word problem states that something is twice or two times a number, all it is saying is to multiply your number/variable by 2. Variables are used for numbers that are unknown. Usually, your goal is to solve for the variable in order to get what number the variable is replacing. For example, if a problem states that "twice the number x equals 14" you could...http://www.enotes.com/homework-help/twice-number-x-470096Thu, 24 Jul 2014 17:47:20 PST3a. If you wanted it to be absolutely certain that you would get a red...
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3a. If you wanted it to be absolutely certain that you would get a red counter, you would put 0 blue counters in the bag. Even one blue counter would make a slight chance for you to not get red. 3b. If you wanted a 50/50 chance, 50% that you'd get red and 50% that you'd get blue, you would want an equal amount of red and blue counters. Since you have 7 red, you would need to add 7 blue to your bag. 3c. If you wanted a 1/3 chance to get a red...http://www.enotes.com/homework-help/maths-question-3-4-470092Thu, 24 Jul 2014 17:40:49 PSTProbability is about the chances of something happening. In the...
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Probability is about the chances of something happening. In the problems that are featured on the assignment page, you are looking at different situations in which the focus lies in the chances of an outcome being determined. For the tasks in the first question, we are looking at a situation in which we start off with seven red counters in a bag. From that point, the questions move into asking clarification based on terms. When looking...http://www.enotes.com/homework-help/maths-question-3-4-470092#2Thu, 24 Jul 2014 09:03:25 PSTThe number "x" is represented as a letter because it is a variable. This...
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The number "x" is represented as a letter because it is a variable. This is the idea of the type of math that is named algebra. Replacing the variables with single letters (sometimes English alphabet, sometimes Greek alphabet - because the Greeks had a big role in inventing algebra, so we still use their alphabet today) is a shorthand. When we work with long or complicated expressions involving one or more variables, this shorthand makes it...http://www.enotes.com/homework-help/twice-number-x-470096#3Thu, 24 Jul 2014 08:50:35 PSTA pentagon has five sides to it. The root word penta- is Latin for five...
http://www.enotes.com/homework-help/how-many-sides-does-pentagon-have-90021
A pentagon has five sides to it. The root word penta- is Latin for five so pentagon means five sided figure. Tri- is 3, quad- is 4, penta- is 5, hexa- is 6, hepta- is 7, octo is 8, Nona is 9, deca is 10 and dodeca is 12 and so on.http://www.enotes.com/homework-help/how-many-sides-does-pentagon-have-90021Thu, 24 Jul 2014 00:34:25 PSTMath is very important in our lives because it is everywhere we go. In...
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Math is very important in our lives because it is everywhere we go. In everyday life simple math is used to do thing such as counting items, adding totals or calculating 20℅ off your new dress with a coupon. In the workplace whether you are a mathematician using calculus or a cashier totaling orders or change math is necessary in all fieldshttp://www.enotes.com/homework-help/why-math-such-an-important-part-our-lives-389103Thu, 24 Jul 2014 00:26:48 PSTTranslate the written/verbal expression "twice a number x" into...
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Translate the written/verbal expression "twice a number x" into mathematical/symbolic notation: Twice a quantity usually indicates to take two of the things in question; usually this indicates to multiply by 2. Thus "twice a number x" can be written symbolically as 2x. If this is part of a problem, say twice a number x is 6, then we can rewrite algebraically as 2x=6; dividing both sides by 2 yields x=3. And we can see that, indeed, twice the...http://www.enotes.com/homework-help/twice-number-x-470096#4Wed, 23 Jul 2014 17:29:37 PSTWhat does the phrase "Twice a number x" mean? Why do we replace numbers...
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What does the phrase "Twice a number x" mean? Why do we replace numbers with letters/symbols?http://www.enotes.com/homework-help/twice-number-x-470096#5July 23, 2014, 5:16 pm PSTTo use u substitution, you set u = 3x + 4, then take the derivative of...
http://www.enotes.com/homework-help/how-can-find-int-cos-3x-4-by-using-substitution-465175
To use u substitution, you set u = 3x + 4, then take the derivative of u, which is du = 3dx, which means dx = du/3. Plug these back into the original integration. (1/3) `int` cos(u)du Then solve: (1/3)sin(u) + C Plug what u is back in: (1/3)sin(3x + 4) + Chttp://www.enotes.com/homework-help/how-can-find-int-cos-3x-4-by-using-substitution-465175Wed, 23 Jul 2014 14:56:09 PSTI need help to work out all questions on the assignment page.
http://www.enotes.com/homework-help/maths-question-3-4-470092
I need help to work out all questions on the assignment page.http://www.enotes.com/homework-help/maths-question-3-4-470092#6July 23, 2014, 9:56 am PSTUse the equation 2 ( 60 ) + 2w = 170 with " w " as the width . 2 ( 60 )...
http://www.enotes.com/homework-help/rectangle-has-perimeter-170-centimeters-length-60-180361
Use the equation 2 ( 60 ) + 2w = 170 with " w " as the width . 2 ( 60 ) + 2w = 170 now multiply 2 with 60 . By multiplying 2 with 60 , you should get : 120 + 2w = 170 now subtract 120 on both sides By subtracting 120 on both sides , you should have : 2w = 50 now divide both sides by 2 . By dividing both sides by 2 , you should get : w = 25 Since width is 25 and length is 60 , find the area by multiplying 25 with 60 Area = 1500 cm ^2http://www.enotes.com/homework-help/rectangle-has-perimeter-170-centimeters-length-60-180361Wed, 23 Jul 2014 05:29:04 PSTIt doesn't look possible to do #4 with the information given. You just...
http://www.enotes.com/homework-help/1-function-defined-by-which-two-intervals-function-469596
It doesn't look possible to do #4 with the information given. You just state "the parabola" but don't give any points on or equation for the parabola.http://www.enotes.com/homework-help/1-function-defined-by-which-two-intervals-function-469596Tue, 22 Jul 2014 22:41:23 PST