1.

The value of x satisfying the equation `cos^(-1)3x+sin^(-1)2x=pi` isA. `x=(1)/(sqrt(3))`B. `x=(-1)/(sqrt(3))`C. `x=(-1)/(sqrt(3))`D. none of these

Answer» Correct Answer - D
`sin^(-1)2x=pi-cos^(-1)3x`
`rArr sin^(-1)2x=cos^(-1)(-3x)`
`rArr sqrt(1-4x^(2))=-3x(xlt 0)`
`rArr x^(2)=(1)/(13)`
`rArr x=(-1)/(sqrt(13))`
But for `x lt 0, pi//2 lt cos^(-1)3x lt pi` and `-pi//2 lt sin^(-1)2x lt 0`
`therefore L.H.S. ne pi`
Hence, equation has no solution.


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