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Solve cos 7x= sin 3x...

Solve cos 7x= sin 3x

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cos 7x = cos3x
`rArr cos 7x = cos(pi/2-3x)`
`rArr 7x = 2npi +- (pi/2-3x)`
Taking Positive sign, we get
`10x=2npi + pi/2 =(4n+1)pi/2`
`therefore x=(4n+1)pi/20, n int Z`
`rArr x = (4n-1)pi/8, n int Z`
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