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The 12th Term of the G.P. 1 a 3 X 3 , a X , a 5 X 5 , . . .

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प्रश्न

Find :

the 12th term of the G.P.

\[\frac{1}{a^3 x^3}, ax, a^5 x^5 , . . .\]

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उत्तर

Here,

\[\text { First term, } a = \frac{1}{a^3 x^3}\]

\[\text { Common ratio }, r = \frac{a_2}{a_1} = \frac{ax}{\frac{1}{a^3 x^3}} = a^4 x^4 \]

\[ \therefore 12th \text { term } = a_{12} = a r^{(12 - 1)} = \frac{1}{a^3 x^3}( a^4 x^4 )^{11} = a^{41} x^{41} \]

\[\text { Thus, the 12th term of the given GP is } a^{41} x^{41} .\]

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अध्याय 20: Geometric Progression - Exercise 20.1 [पृष्ठ १०]

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आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 20 Geometric Progression
Exercise 20.1 | Q 3.4 | पृष्ठ १०

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