Question

sin60°cos30°-cos150°sin120°=3by2

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Answer 1

Step-by-step explanation:

Sin120= sin(90+30)=cos30= sqrt(3)/2. Cos150= cos(180–30)= - cos30= - sqrt(3)/2. Cos240= cos(180+60)= - cos60= -1/2

Answer 2

sin60°=√3/2,

cos30°=√3/2

cos150°= -√3/2,

sin120°=√3/2

(√3/2×√3/2)-(√-3/2×√3/2)=3/2

(3/4)-(-3/4)=3/2

3/4+3/4=3/2

6/4=3/2

3/2=3/2