The value of x for the maximum value of √3cosx+sinx is
300
450
600
900
Let f(x) = √3cosx+sinx
⇒ f(x) = 2(√32cosx+12sinx) = 2sin(x+π3)
But -1 ≤ sin(x+π3) ≤ 1
Hence, f(x) is maximum, if x + π3 = 90∘ ⇒ x = 30∘.
Prove that f(x)=sinx+√3cosx has maximum value at x=π6.