Top answers

Find the equation of the tangent to the curve y = x^2-2x-3 at x=-1

First we find the gradient by differentiation. Differentiating the expression for the curve gives dy/dx=2x-2. Subbing in x=-1 gives dy/dx=-4 so the gradient of the line is -4. To find the y intercept, we use...
CR
Answered by Caleb R. • Maths tutor
6237 Views

evaluate the integral 2x/((9+x^2)^1/2) between -2 and 0

One approach would be to use integration by parts, as we have two functions of x within the integral. This approach would get you to the answer but would be more difficult and convoluted than necessary. One ...
AF
Answered by Aiden F. • Maths tutor
4371 Views

Expand the brackets (x-3)(x+4)

When dealing with questions to do with expanding brackets, you must multiply every term in one bracket with all the others in the second bracket. So for this question, we can see we have 4 terms in total: Le...
AA
Answered by Ameer A. • Maths tutor
6545 Views

Solve these simultaneous equations. 2x + y = 18 x - y = 6

With simultaneous equations there is more than one unknown. First we’ll get one unknown on its own so we rearrange the bottom equation to get x on its own. By adding y to each side of the equation this leave...
LS
Answered by Lizzie S. • Maths tutor
6322 Views

Find the value of x: x^2-3x-3=1

To begin this question you need to bring all of the terms to one side, so the equation equals 0. It is easiest to do this by subtracting 1 from each side.x^2-3x-3-1=1-1x^2-3x-4=0Now we need to factorise the ...
EH
Answered by Emma H. • Maths tutor
4010 Views