Top answers

Maths
All levels

Give the first and second derivative of the function f(x) = 5/x - 9x + 4

  1. 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^...
HB
Answered by Harvey B. Maths tutor
2902 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 -...

SA
Answered by Sophie A. Maths tutor
3524 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...

SN
Answered by Sean N. Maths tutor
1205 Views

Factorise 100-x^2

Via inspection, one can factorise this via the difference of squares; since a^2-b^2 = (a+b)(a-b), therefore:100-x^2 = (10-x)(10+x)

HM
Answered by Howard M. Maths tutor
6536 Views

Via the product rule, or otherwise, differentiate 'y = xsin(x)'.

SInce, for y = uv, dy/dx = uv' + vu', where u' = du/dx, therefore:dy/dx = (1sin(x)) + (xcos(x)) = sin(x) + xcos(x)

HM
Answered by Howard M. Maths tutor
3095 Views

We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning