Prove that 59×59×59−9×9×959×59+59×9+9×9=50.
ANSWER: 59×59×59−9×9×959×59+59×9+9×9 =(593−93)592+59×9+92 We know a3+b3=(a+b)(a2+b2−ab) Here a=59,b=9 So,(59−9)(592+92+59×9)592+92+59×9=59−9=50 :RHS