Question

已知函数f (x)=1/2sinx+根号3/2cosx,x属于R.

Answer 1

(1)

f(x)=(1/2)sinx+(√3/2)cosx

=sin(x+π/3)

最小正周期=2π

值域=[-1,1]

(2)

f(A)=√3/2

sin(A+π/3)=√3/2

A+π/3=2π/3

A=π/3

a=√3( b/2)

a/sinA = b/sinB

a/sin(π/3) = (2a/√3)/sinB

sinB =1

B=π/2

C= π-A-B

= π/6