Question

using identities find the value of following​

Answer 1

Answer:

I) 999²=(1000-1)²

This is in the form of (a-b) ²=a²-2ab+b²

(1000-1)²=1000²-2(1000)(1)+1²

=1000000-2000+1

999²= 998001

ii) 36²-12²

This is in the form of a²-b²=(a+b) (a-b)

36²-12²=(36+12)(36-12)

=(48)(24)

36²-12²=1152

iii) (2x+5y)(2x+5y)=(2x+5y)²

This is in the form of (a+b)²=a²+2ab+b²

(2x+5y)²=(2x)²+2(2x)(5y)+(5y)²

(2x+5y)²=4x²+20xy+25y²