Question

(x + 1)(x - 1)
i got x^2 - 2?

Answer 1

oops

Answer 2

\[1\times -1\] is the last term

Answer 3

what on earth?

Answer 4

sorry but this is not right.

Answer 5

no i know its not right

Answer 6

imran will explain why. but the last term is not -2

Answer 7

well even that is wrong. dang

Answer 8

x*x-1*x+1*x -1*1

Answer 9

x*x -1*x +1*x -1*1

Answer 10

\[(x+1)(x-1)=x(x-1)+1(x-1)=x^2-x+x-1=x^2-1\]

Answer 11

for example if
\[x=10\] you know that
\[(10+1)(10-1)=11\times 9=99=10^2-1\]