Question

c² - 20d-d Solve this question using the formula of ( a²+2ab+ b²) (a²-2ab-b²)​

Answer 1

Answer:

What is the formula for (a-b-c)²?

We know the algebraic identity,

( x + y + z )²

= x² + y² + z² + 2xy + 2yz + 2zx

Now ,

( a - b - c )²

=[ a² + ( - b )² + ( -c )² ]²

=a²+(-b)²+(-c)²+2a(-b)+2(-b)(-c)+2(-c)a

= a² + b² + c² - 2ab + 2bc - 2ca