Help qith solving question

• May 26th 2011, 05:18 PM
instantaneo
Help qith solving question
(2-10 √(1÷25+h))/(h√(1÷25+h))x(2+10√(1÷25+h))/(2+10√(1÷25+h))

need to know how the numerator equals -100h. I tried it but i couldn't see how it happens!
• May 26th 2011, 05:21 PM
Chris L T521
Quote:

Originally Posted by instantaneo
(2-10 √(1÷25+h))/(h√(1÷25+h))x(2+10√(1÷25+h))/(2+10√(1÷25+h))

need to know how the numerator equals -100h. I tried it but i couldn't see how it happens!

Spoiler:
$(a-b)(a+b) = a^2-b^2$
• May 26th 2011, 05:43 PM
instantaneo
thanks!