Question

सरळरूप द्या: (5x - 7y)³ + (5x + 7y)³

Answer 1

$25 {x}^{3} - 49 {y}^{3}$
it's your answer
I hope it will help you

Answer 2

(5x - 7y)³ + (5x + 7y)³

answer. ( a - b )³ + ( a + b )³ = 2[ a³ + 3ab² ]

Here ,

a = 5x , b = 7y 

( 5x - 7y )³ + ( 5x + 7y )³

= 2 [ ( 5x )³ + 3 × 5x × ( 7y )² ]

= 2 [ 125x³ + 15 x × 49y² ]

= 2[ 125 x³ + 735xy² ]

= 250x³ + 1470xy²

I hope this helps you.