Question

9. Verify (1) x³ + y³ = (x + y) (x² - xy + y²) (ii) x³ - y³ = (x - y) (x² + xy + y²)
using some non-zero positive integers and check by actual multiplication. Can you call
these as identites?​

Answer 1

Answer:

(i)

Let, x=1 , y=2

x³ + y³ =1³+2³= 1+8=9

(x + y) (x² - xy + y²)=(1+2)(1²-1*2+2²)=3*3=9

(ii)

Let, x= 1, y=2

x³-y³=1³-2³=1-8= -7

(x - y) (x² + xy + y²)=(1-2)(1²+1*2+2²)=-1*7= -7

both i & ii are identities.