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Question-9929




Question Number 9929 by ridwan balatif last updated on 16/Jan/17
Answered by mrW1 last updated on 18/Jan/17
lim_(x→0)  ((sin 4x∙tan^2  3x+6x^2 )/(2x^2 +sin 3x∙cos 2x))  =lim_(x→0)  ((4(((sin 4x)/(4x)))tan^2  3x+6x)/(2x+3(((sin 3x)/(3x)))cos 2x))  =((4×1×0+0)/(0+3×1×1))=(0/3)  =0  ⇒Answer A
$$\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\mathrm{sin}\:\mathrm{4}{x}\centerdot\mathrm{tan}^{\mathrm{2}} \:\mathrm{3}{x}+\mathrm{6}{x}^{\mathrm{2}} }{\mathrm{2}{x}^{\mathrm{2}} +\mathrm{sin}\:\mathrm{3}{x}\centerdot\mathrm{cos}\:\mathrm{2}{x}} \\ $$$$=\underset{{x}\rightarrow\mathrm{0}} {\mathrm{lim}}\:\frac{\mathrm{4}\left(\frac{\mathrm{sin}\:\mathrm{4}{x}}{\mathrm{4}{x}}\right)\mathrm{tan}^{\mathrm{2}} \:\mathrm{3}{x}+\mathrm{6}{x}}{\mathrm{2}{x}+\mathrm{3}\left(\frac{\mathrm{sin}\:\mathrm{3}{x}}{\mathrm{3}{x}}\right)\mathrm{cos}\:\mathrm{2}{x}} \\ $$$$=\frac{\mathrm{4}×\mathrm{1}×\mathrm{0}+\mathrm{0}}{\mathrm{0}+\mathrm{3}×\mathrm{1}×\mathrm{1}}=\frac{\mathrm{0}}{\mathrm{3}} \\ $$$$=\mathrm{0} \\ $$$$\Rightarrow{Answer}\:{A} \\ $$
Commented by ridwan balatif last updated on 18/Jan/17
thank you sir
$$\mathrm{thank}\:\mathrm{you}\:\mathrm{sir} \\ $$

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