Question

Without actually calculating the cubes(by using suitable identity) ,find the value of (-12)³+(7)³+(5)³​

Answer 1

$- 12 + 7 + 5 = 0$

$we \: know \: if \: a + b + c = 0 \\ {a}^{3} + {b}^{3} + {c}^{3} = 3abc$

${( - 12)}^{3} + {7}^{3} + {5}^{3} = 3( - 12)(7)(5)$

$- 1260$