Search our library of Maths GCSE questions

Top answers

Maths

GCSE

How to factorise the expression x^2 + 8x + 15

We need to get the quadratic expression into the form (x + a)(x + b). If we expand this expression using FOIL, we see that the resulting expression is x² + (a+b)x + ab. We can now find a and b ...

Answered by Charlotte S. • Maths tutor

3330 Views

How do I calculate negative powers?

The power of a number indicates how many times that number must be multiplied by itself. If the power is a negative, this means that the number (or the base) is a fraction, with the base as a denominator....

Answered by Molly N. • Maths tutor

9697 Views

f(x) = 4x - m, g(x) = mx + 11, fg(x) = 8x + n. m and n are constants. Find the value of n.

If f(x) = 4x - m, and g(x) = mx +11, then the combined functions are: fg(x) = 4(mx +11) -m, or expanded to fg(x) = 4mx + 44 - m.

We are told that this function of 'f' and 'g' can also be written as...

Answered by Angus B. • Maths tutor

4235 Views

Expand and simplify the following expression: (2x-1)(3x+2)

Use a double-bracket expansion method such as FOIL (first, outer, inner, last). If you don't know FOIL or how to expand double brackets, don't worry, I will explain it to you in the session.