if `a=cos 2 and b =sin7,` thenA. `a gt0, b gt0`B. `ab lt0`C. `a gtb`D. – InterviewSolution

InterviewSolution

1.	if `a=cos 2 and b =sin7,` thenA. `a gt0, b gt0`B. `ab lt0`C. `a gtb`D. `a ltb`
Answer» Correct Answer - B We have, `(pi)/(2)le2^(c)le(3pi)/(4)and 2pilt7^(c)(5pi)/(2)` `implies2^(c)"is in second quadrant and"7^(c) "is in first quadrnat"` `impliesa =cos2^(c)lt0and b=sin7^(c)gt0` `impliesab lt0`

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