Question

If at+b+c =5 and ab+bc+ca=10 , then prove that a
${a}^{3} + {b}^{3 +} + {c}^{3} - 3abc = - 25$
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Answer 1

Answer:

We know that,

<br>

<br>

<br> Now, a+b+c=5 <br> Squaring both sides, we get <br>

<br>

<br>

<br>

<br> Now,

<br> =5(5-10)=5(-5)=-25