f(x)=1+2sin x+3cos ²x[0,2p÷3) find max value of function
Miss Pooja , 10 Years ago
Grade 12th pass
1 Answers
Arun Kumar
Last Activity: 10 Years ago
Hello Student,
f(x)=1+2sin x+3cos ²x f(x)=1+2sin x+ 3 (1 - sin2x) f(x) = -3sin2x + 2 sin x + 4 df(x)/dx = -6sinxcosx + 2cosx = 0 =>sin x = 1/3 or cosx = 0 d/dx(df(x)/dx) = -3cos2x - 2sinx <0 for sin x = 1/3 >0 for cos x = 0 =>x = sin-1 (1/3) maxima =>f(x)_{max} is 13/3