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What is the chain rule?

Up until now you may have been given functions like f(x)= 7x^3 +cos(x) and been told just to differentiate. What your teacher really meant was to differentiate with respect to x. The chain rule allows us to ...
JM
Answered by James M. Maths tutor
3663 Views

Find the integral of 4sqrt(x) - 6/x^3.

The easiest way to do this is to break the integral up into it's separate parts. We have:integral of 4sqrt(x)andintegral of -6/x^3 Both of which have constants that can be taken out, i.e. 4 and 6, respective...
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Answered by Sam P. Maths tutor
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Give the first and second derivative of the function f(x) = 5/x - 9x + 4

Re-write f(x) as f(x) = 5x^(-1) - 9x + 42) Find first derivative as usual - multiply each term by it's power and subtract 1 from the power:f'(x) = (-1)(5x^(-2)) - (1)(9)Simplify to get f'(x) = -5/x^(2) - 9Fi...
HB
Answered by Harvey B. Maths tutor
3336 Views

Solve the simultaneous equations: 5x + y = 21 and x - 3y = 9

x = 4.5y = -1.5To answer this question, first, rearrange the first equation to make y the subject: 5x + y = 21 --> y = 21 - 5xYou can now substitute this value of y into the second equation: x - 3(21 - 5x...
SA
Answered by Sophie A. Maths tutor
4127 Views

How do you solve integrals which are the result of a chain rule e.g. the integral of sin(2x+1)

∫sin(2x + 1)dx[newline]In this case the easiest way to solve the integral is to perform a substitution. The substitution should reduce the integral to something you can solve. In this case we will[newline]le...
SN
Answered by Sean N. Maths tutor
1652 Views