If the coefficients of x^2 and x^3 in the exp | vedclass

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(D) The general term in the expansion of $(3 + ax)^9$ is given by $T_{r+1} = {}^9C_r (3)^{9-r} (ax)^r = {}^9C_r (3)^{9-r} a^r x^r$.The coefficient of

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$\frac{9}{7}$

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(D) The general term in the expansion of $(3 + ax)^9$ is given by $T_{r+1} = {}^9C_r (3)^{9-r} (ax)^r = {}^9C_r (3)^{9-r} a^r x^r$.The coefficient of $x^r$ is ${}^9C_r 3^{9-r} a^r$.For $r=2$,the coefficient of $x^2$ is ${}^9C_2 3^7 a^2$.For $r=3$,the coefficient of $x^3$ is ${}^9C_3 3^6 a^3$.Given that these coefficients are equal:${}^9C_2 3^7 a^2 = {}^9C_3 3^6 a^3$Dividing both sides by $3^6 a^2$ (assuming $a 
eq 0$):${}^9C_2 \cdot 3 = {}^9C_3 \cdot a$$\frac{9 	imes 8}{2 	imes 1} 	imes 3 = \frac{9 	imes 8 	imes 7}{3 	imes 2 	imes 1} 	imes a$$36 	imes 3 = 84 	imes a$$108 = 84a$$a = \frac{108}{84} = \frac{9}{7}$.

If the coefficients of $x^2$ and $x^3$ in the expansion of $(3 + ax)^9$ are the same,then the value of $a$ is

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