Question

a=2^1/3-2^-1/3 prove that 2a^3+6a-3=0​

Answer 1

Answer:

Given that a=21/3−2−1/3, we want to determine the value of 2a3+6a−3.

Let 21/3=p⇒p3=2 and 1p3=12.

⇒a=p−1p.

⇒a3=(p−1p)3=p3−3p+3p−1p3

=p3−1p3−3(p−1p)=2−12−3a=32−3a.

⇒2a3+6a−3=2(32−3a)+6a−3

=3−6a+6a−3=0.