Class 9th math Review Exercise 1 solution english PCTB

\((ix)\) The product of \((3+\sqrt{5})\)\((3-\sqrt{5})\) is:

Option B : Rational Number

Explanation:

\[
\begin{align*}
&=\left( 3+\sqrt{5}\right)\left( 3-\sqrt{5}\right)\\
&=3^{2} -\left(\sqrt{5}\right)^{2}\\
&=9-5\\
&=4\\
\end{align*}
\]

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