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Grade 12th passIntegral Calculus

integral one divided by 1+cosx
limits are 0 to pie/4

Profile image of Ranga Manchikanti
9 Years agoGrade 12th pass
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1 Answer

Profile image of Arijit
9 Years ago
1/1+cosx=1/(1+2cos2x/2-1)=1/2sec2x/2 
let tan(x/2)=z
take diff at both sides
½ sec2x/2dx=dz
now∫0(pi/4)dz=[z]0(pi/4)=[tan(x/2)]0(pi/4)=tan(pi/8)