Top answers

Write 16× 8^2x as a power of 2 in terms of x.

16 = 2 4 8 2x = (2 3 ) 2x = 2 6x Therefore, 16x8 2x = 2 4 x 2 6x = 2 4+6x
XY
Answered by Xixi Y. • Maths tutor
8604 Views

A curve has equation y = 20x −x^2 −2x^3 . The curve has a stationary point at the point M where x = −2. Find the x-coordinate of the other stationary point of the curve.

dy/dx = 20 - 2x - 6x 2 = -6x 2 - 2x + 20 which factorises to dy/dx = (10 - 6x)(2 + x). This shows that x=-2 and x=10/6=5/3 are stationary points of y = 20x −x 2 −2x 3 .
XY
Answered by Xixi Y. • Maths tutor
6316 Views

How to prove that Integral S 1/(a^2+x^2) dx= 1/a arctan(x/a) + C ?

In order to answer this question, at first we need to use the method of substitution. That means, we're trying to replace x with a different variable u. Lets use the substitution of x = a tan u, then du/dx =...
JW
Answered by Judyta W. • Maths tutor
8918 Views

Solve the following simultaneous equations: x^2 + 2y = 9, and y = x + 3.

Label the two equations as the following: x 2 + 2y = 9 y = x + 3 Equation 2 can be substituted into equation 1, giving: x 2 + 2( x + 3 ) = 9Expanding the brackets and subtracting 9 from both sides means equa...
XB
Answered by Ximena B. • Maths tutor
4599 Views

How do I solve simultaneous equations by substitution?

You can solve simultaneous equations by either substitution or elimination. Say we have the equations:(1) 8y + 6x = 24 and (2) 2y - x = 6SUBSTITUTION METHODFirst, you need to find x in terms of y (or y in te...
JN
Answered by Joshua N. • Maths tutor
3544 Views