math
posted by Fin on .
(10x  1)^2
Does it = 100x + 1

Memorizing the following identities will help you with similar problems:
(a+b)^2=a^2+2ab+b^2
(ab)^2=a^22ab+b^2
Now put a=10x, b=1 and apply to (ab)^2
(10x  1)^2
=(10x)^2 2(10x*))+(1)^2
=100x²20x+1