Top answers

Find the equation of the tangent at x=1 for the curve y=(4x^2+1)^3

The tangent is the straight line passing through x=1, touching the curve only at that point. For x=1, y=(4+1)^3=125 Using the chain rule we obtain dy/dx = 3 8x (4x^2+1)^2. To then get the gradient of the tan...
JH
Answered by Jacob H. • Maths tutor
4121 Views

If the fourth term in an arithmetic sequence is, u4 = 12.5, the tenth is u10 = 27.5. Find the common difference and the 20th term.

The equations for an arithmetic sequences are 1) Un = u1 + (n - 1)d 2) Sn = n/2(2*u1 + (n-1)d) 3) Sn = n/2(u1 + un) The first step is to calculate the common difference, d. This is done using the first equat...
NK
Answered by Ndalukile K. • Maths tutor
3157 Views

Solve these simultaneous equations: 3y + x = 18 and x - 4y = -10.

Write x in terms of y using one of the equations. Then substitute it in the second equation, which is then only in terms of y. Find y. Then you can easily find x. Answer: x = 6 and y = 4.
TE
Answered by Tess E. • Maths tutor
3832 Views

How do you solve simultaneous equations?

The easiest way to solve simultaneous equations is by elimination. This is the idea of cancelling out one of your variables, the X or Y so that you can solve the remaining variable and then substitute this a...
BH
Answered by Ben H. • Maths tutor
4216 Views

Expand (x+4)(x+3).

To answer this you multiply everything in the left bracket by everything in the right bracket, so rewrite the equation as x(x+3)+4(x+3). Then you can expand each more easily: x(x+3) = x 2 +3x 4(x+3) = 4x+4×3...
ED
Answered by Elliot D. • Maths tutor
32268 Views