How to do this question?

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1 Answer
Dec 4, 2017

x=1.571,3.309,6.116

Explanation:

csc^2x+5cscx-6=0 can be factorized as under

csc^2x+6cscx-cscx-6=0

or cscx(cscx+6)-1(cscx+6)=0

or (cscx-1)(cscx+6)=0

i.e. either cscx-1=0 i.e. cscx=1 and x=pi/2=1.571

or cscx+6=0

i.e. cscx=-6 i.e. x=6.116 or 3.309 (in radians)