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if a=cos 2 and b =sin7, then...

if `a=cos 2 and b =sin7,` then

A

`a gt0, b gt0`

B

`ab lt0`

C

`a gtb`

D

`a ltb`

Text Solution

Verified by Experts

The correct Answer is:
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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