How to do this question?

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1 Answer
Dec 4, 2017

x=1.571,3.309,6.116

Explanation:

csc2x+5cscx6=0 can be factorized as under

csc2x+6cscxcscx6=0

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

or (cscx1)(cscx+6)=0

i.e. either cscx1=0 i.e. cscx=1 and x=π2=1.571

or cscx+6=0

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