Question

{0.5^4 - 0.4^4}/{0.5^2 + 0.4^2} is?

Answer 1

Hope it helps.... :)

Answer 2

$\dfrac{0.5^4 - 0.4^4}{0.5^2 + 0.4^2} = \dfrac{(0.5^2)^2 - (0.4^2)^2}{0.5^2 + 0.4^2}$

Write it as the difference between two perfect square:

$\dfrac{0.5^4 - 0.4^4}{0.5^2 + 0.4^2}= \dfrac{(0.5^2 + 0.4^2)(0.5^2 - 0.4^2)}{0.5^2 + 0.4^2}$

Cancel out common factors:

$\dfrac{0.5^4 - 0.4^4}{0.5^2 + 0.4^2}= 0.5^2 - 0.4^2$

Evaluate each exponents:

$\dfrac{0.5^4 - 0.4^4}{0.5^2 + 0.4^2}=0.25 - 0.16$

Subtract:

$\dfrac{0.5^4 - 0.4^4}{0.5^2 + 0.4^2} =0.09$