If $$(2a-1)^2+(4b-3)^2+(4c+5)^2=0$$, Then the value of $$\frac{a^3+b^3+c^3-3abc}{a^2+b^2+c^2}$$ is:
Given : $$(2a-1)^2+(4b-3)^2+(4c+5)^2=0$$
$$\because$$ Sum of 3 positive terms is 0, then each term is equal to '0'.
=> $$2a-1=0$$
=> $$a=\frac{1}{2}=\frac{2}{4}$$
Similarly, $$b=\frac{3}{4}$$ and $$c=\frac{-5}{4}$$
Now, $$(a+b+c)=\frac{2}{4}+\frac{3}{4}+(\frac{-5}{4})=0$$ --------------(i)
Using, $$a^3+b^3+c^3-3abc=(a+b+c)(a^2+b^2+c^2-ab-bc-ac)$$
=> $$a^3+b^3+c^3-3abc=(0)(a^2+b^2+c^2-ab-bc-ac)$$ Â Â [Using equation (i)]
=>Â $$a^3+b^3+c^3-3abc=0$$ --------------(ii)
To find : $$\frac{a^3+b^3+c^3-3abc}{a^2+b^2+c^2}$$
=Â $$\frac{0}{a^2+b^2+c^2}=0$$ Â Â Â Â [Using equation (ii)]
=> Ans - (D)
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