Question

Find the value using suitable identity......



Q.no.20
Thnx

Answer 1

Answer:

$70^{3}-50^{3}-20^{3}=210000$

Step-by-step explanation:

$If \: x+y+z =0 \:then \\x^{3}+y^{3}+z^{3}=3xyz$

Given 70³-50³-20³

= 70³ + (-50)³ + (-20)³

$Here , x = 70, \:y = -50,\:z =-20$

$x+y+z = 70-50-20=0$

$=3\times 70\times(-50)\times (-20)\\=210000$

Therefore,

$70^{3}-50^{3}-20^{3}=210000$

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