Question
Find the products: Multiply $-\frac{2}{3}\text{a}^2\text{b by }\frac{6}{5}\text{a}^3\text{b}^2$ and verify your result for $a = 2$ and $b = 3.$

Answer

$\frac{-2}{3}\text{a}^2\text{b}\times \frac{6}{5}\text{a}^3\text{b}^2$
$=\frac{-2}{3}\times \frac{6}{5}\text{a}^2\times \text{a}^3\times \text{b}\times \text{b}^2$
$=\frac{-4}{5}\text{a}^{2+3}\text{b}^{1+2}$
$=\frac{-4}{5}\text{a}^5\text{b}^3$
Verification:
Now if $a = 2, b = 3$, then $-\frac{2}{3}\text{a}^2\text{b}=\frac{-2}{3}\times (2)^2\times 3$
$=\frac{-2}{3}\times 4\times 3$
$=-8$
$\frac{6}{5}\text{a}^3\text{b}^2=\frac{6}{5}\times (2)^3\times (3)^2$
$=\frac{6}{5}\times 2\times 2\times 2\times 3\times 3$
$=\frac{6}{5}\times 8\times 9=\frac{432}{5}$
$\therefore \text{L.H.S} = -8 \times \frac{432}{5}$
$=\frac{-3456}{5}$
$\text{R.H.S}=\frac{-4}{5}\text{a}^5\text{b}^3=\frac{-4}{5}(2)^5(3)^3$
$=\frac{-4}{5}(2\times2\times2\times2\times2)\times3\times3\times3$
$=\frac{-4}{5}\times32\times27$
$=\frac{-4\times864}{5}=\frac{-3456}{5}$
$\therefore \frac{-3456}{5}=\frac{-3456}{5}$
$\text{L.H.S.}= \text{R.H.S}$

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