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If cos x=-3/5a n d\ x lies in IIInd quad...

If `cos x=-3/5a n d\ x` lies in IIInd quadrant, find the values of `sin2x\ a n dsin(x/2)dot`

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Verified by Experts

awe know that
`=>cos2x=2cos^2x-1`
`=>cos2x+1=2cos^2x`
`=>(cos2x+1)/2=cos^2x`
`=>sqrt((cos2x+1)/2)=cos2x`
So,
`=>cos(x/2)=sqrt((cosx+1)/2)`
...
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  2. If cos x=\ -3/5a n d\ x lies in the IIIrd quadrant, find the values of...

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  3. If cos x=-3/5a n d\ x lies in IIInd quadrant, find the values of sin2x...

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  6. If costheta=4/5 and theta is acute, find the tan2theta

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