The value of $\frac{[(5.4)^3-0.064]}{[(5.4)^2+2.16+0.16]}$ is _________.
Answer & explanation
Correct answer: option 1
a3 - b3 = ( a - b ) ( a2 + b2 + ab )
( a - b ) = \(\frac{a^3 - b^3}{a^2 + b^2 + ab }\)
$\frac{[(5.4)^3-0.064]}{[(5.4)^2+2.16+0.16]}$ this can be written as =
$\frac{[(5.4)^3-(0.4)^3]}{[(5.4)^2+2.16+(0.4)^2]}$
By comparing the above equation with the given formula we can conclude that,
a = 5.4
and b = 0.4
So the value of $\frac{[(5.4)^3-(0.4)^3]}{[(5.4)^2+2.16+(0.4)^2]}$ = 5.4 - 0.4 = 5