Question

using identity solve (-20)³+(15)³+(5)³​

Answer 1

a^3 + b^3 + c^3 = 0

if a+b+c =0

as we know,

=> -20 + 15 + 5

=> 0

since the answer is 0

Answer 2

$\textbf{\underline{\red{Step by step Explanation:-}}}$

$\textit{\underline{Given,,}}$

$\mathtt{a=-20,,b=15,,c=5}$

$\textbf{\underline{Hence,,}}$

$\mathtt{a+b+c=-20+15+5}$

$\mathtt{=-20+20}$

$\mathtt{=-0}$

$\textit{\underline{Using Identity,,}}$

$\mathtt{a^{3}+b^{3}+c^{3}=3abc}$

$\mathtt{=(-20)^{3}+(15)^{3}+(5)^{3}}$

$\mathtt{=3\times(-20)(15)(5)}$

$\mathtt{=(-60)(75)}$

$\mathtt{=-4500}$

$\textit{\underline{Check,,}}$

$\mathtt{(-20)^{3}+(15)^{3}+(5)^{3}=-8000+3375+125}$

$\mathtt{=-8000+3500}$

$\mathtt{=-4500}$

$\textit{Hence proved,,}$

$\textbf{\underline{\pink{Hope it helps you..}}}$