Question

using formula (a-b)2=(a2-2ab+b2) evaluate
(689)2​

Answer 1

Answer:

Hey mate Here is your answer

Step-by-step explanation:

Given (689)2 We have (a – b)2 = (a2 – 2ab + b2)(689)2 can be written as 700-11 So here a=700 and b=11 Using the formula, (700 – 11)2 = (7002 – 2 X 700 X 11 + 112) On simplifying we get (700 – 11)2 = (490000 – 15400 +121) (689)2 = 474721Read more on Sarthaks.com - https://www.sarthaks.com/729549/using-the-formula-a-b-2-a-2-2ab-b-2-evaluate-689-2

Answer 2

Answer:

Using identity (a-b) ²=(a²- 2ab-b²)

(689)²= (700-11)²[where a=700,b=-11]

= 700²- 2(700)(-11)+ (-11²)

=4900- (1400)(-11)+121 [-*-=+]

=4900- (-15400) + 121

= 20300+121

= 20421

This is the answer which you want!

thank you!!!