The maximum and minimum values of `6 sin x cos x +4cos` are respective – InterviewSolution

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1.	The maximum and minimum values of `6 sin x cos x +4cos` are respectivelyA. `5 and -5`B. `2sqrt13 and -2 sqrt13`C. `10 and -10`D. none of these
Answer» Correct Answer - A We have, `6 sinx cos x+4cos2x=3sin2x+4cos2x` Now, `-sqrt(3^(2)-4^(2))le3 sin 2x+4 cos 2x lesqrt(3^(2)+4^(2))"for all" x implies-5le6sinx x cosx+4cos2x le5"for all x"` Hence, the maximum and minimum values of `3 sin2x+4cos2xare5and -5` respectively.

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