Calculate (7 + √3)(7 - √3)

(7 + √3)(7 - √3) = 72 + 7√3 - 7√3 - (√3)2 = 49 - 3 = 46Alternatively you can go straight to identifying that this is the difference between two squares, using the fact that (a + b)(a - b) = a2 - b2

IB

Related Maths GCSE answers

All answers ▸

2x + y = 24, x - y = 6


The normal price of the pair of shoes is £28. In a sale the price is reduced by 35%. What is the new price of the shoes?


Solve the simultaneous equations: 4X+6Y=4 and 7X+5Y=12.5


Simplify 7 × e × f × 8