Question

यदि ( a – b ) = 4 , तथा ab = 2 तो, ( a3 – b3) = ?

Answer 1

Answer:

Hence, the value of a³-b³=88.

Step-by-step explanation:

∵a³-b³= (a-b)(a²+ab+ b²) ...(i)

here given, (a-b)=4 and ab =2

(a-b)²=4²

a²-2ab+b²=16

⇒a²+b²-2×2=16

⇒a²+b²=20

Now, substituting the above values in (i)

a³-b³=4×(20+2)=4×22=88