Question

设函数f(x)=sin（x+6分之派）+2sin方二分之x,

Answer 1

sin(x+π/6)=sinxcosπ/6+cosxsinπ/6=根号3/2sinx+1/2cosx

2sin²(x/2)=1-cosx

f(x)=根号3/2sinx+1/2cosx+1-cosx=根号3/2sinx-1/2cosx+1=sin(x-π/6)+1

1、T=2π

2、f(A)=sin(A-π/6)+1=1

A-π/6=0

A=30°

sinA=1/2

a/sinA=1/(1/2)=2

c/sinC=根号3/sinC=2

sinC=根号3/2

C=60°

B=180-60-30=90

b=2