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Evalute sin 60. cos 30 sin +sin 30 .cos 60 what is the value of sin(30-60) what can you conclude​

User Evangelos
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Answer:

See explanations below

Explanation:

evaluate sin 60. cos 30 sin +sin 30 .cos 60 what is the value of sin(30-60) what can you conclude​

According to the trigonometry identity

Sin 30 = 1/2

Sin 60 = √3/2

Cos 30 = √3/2

Cos 60 = 1/2

sin 60. cos 30 +sin 30 .cos 60

= √3/2(√3/2) + 1/2(1/2)

= √9/4 + 1/4

= 3/4 + 1/4

= 4/4

= 1

sin(30-60) = sin30cos60 - cos30sin60

sin(30-60) =1/2(1/2) - √3/2(√3/2)

sin(30-60) = 1/4 - √9/4

sin(30-60) = 1/4 - 3/4

sin(30-60) = (1-3)/4

sin(30-60) = -2/4

sin(30-60) = -1/2

hence the former fraction gives a positive values while the later gives a negative

User SpazzMarticus
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