If `sin2theta=cos3theta` and `theta` is an acute angle , then `sintheta` is equal to
If `sin2theta=cos3theta` and `theta` is an acute angle , then `sintheta` is equal to
A. `(sqrt(5)-1)/(4)`
B. `-((sqrt(5)-1)/(4))`
C. `(sqrt(5)+1)/(4)`
D. `(-sqrt(5)-1)/(4)`
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Correct Answer - A
`sin 2 theta=cos 3theta`
or `2 sin theta cos theta=4cos^(3)theta-cos theta`
or `2sin theta=4(1-sin^(2)theta)-3`
or `4sin^(2)theta+2sin theta-1=0`
or `sin theta=(sqrt(5)-1)/(4)`
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