Solve that following equations : `sec x cos 5x+1=0,` `0 lt x le pi/2` find the value of x

Explanation

`secx*cos5x+1=0`

`(cos5x)/cosx=-1`

`cos5x=-cosx`

`cos5x+cosx=0`

`2cos((5x+x)/2)*cos((5x-x)/2)=0`

`2ocs3x*cos2x=0`

`cos3x=0`

`3x=pi/2,3/2pi`

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