Question

The number of terms in (a+b+c)^4

Answer 1

(a+b+c)^4=(a+b+c)^2+(a+b+c)^2
(a^2+b^2+c^2+2ab+2ac+2bc)+(a^2+b^2+c^2+2ab+2ac+2bc)
=>2a^2+2b^2+2c^2+4ab+4ac+4ca
Therefore the no.of terms r 6