Evaluate the following.
$\frac{(12.5)^3+(7.5)^3}{(12.5)^2+(7.5)^2-12.5×7.5}$
Answer & explanation
Correct answer: option 1
a3 + b3 = ( a + b ) ( a2 + b2 - ab )
( a + b ) = \(\frac{a^3 + b^3}{a^2 + b^2 - ab }\)
$\frac{(12.5)^3+(7.5)^3}{(12.5)^2+(7.5)^2-12.5×7.5}$
By comparing the values of given equation to the formula given above we get to know,
a = 12.5
b = 7.5
So the value of a + b = 12.5 + 7.5 = 20