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sin(alpha-beta), sina=(11)/(12)in the II quadrant, Cos(beta)=(15)/(17) in quadrant IV, sin(alpha-beta)=

User Splintor
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Answer:

Explanation:

To find sin(alpha-beta), we can use the trigonometric identity:

sin(alpha - beta) = sin(alpha)cos(beta) - cos(alpha)sin(beta)

We are given that sin(alpha) = 11/12 in the second quadrant and cos(beta) = 15/17 in the fourth quadrant. We can use the Pythagorean theorem to find sin(beta):

sin^2(beta) + cos^2(beta) = 1

sin(beta) = sqrt(1 - cos^2(beta))

sin(beta) = sqrt(1 - (15/17)^2)

sin(beta) = sqrt(1 - 225/289)

sin(beta) = sqrt(64/289)

sin(beta) = 8/17 (since sin(beta) is positive in the fourth quadrant)

Now we can plug in the values we know into the identity:

sin(alpha - beta) = sin(alpha)cos(beta) - cos(alpha)sin(beta)

sin(alpha - beta) = (11/12)(15/17) - cos(alpha)(8/17)

We still need to find cos(alpha), which we can do using the Pythagorean identity:

sin^2(alpha) + cos^2(alpha) = 1

cos(alpha) = sqrt(1 - sin^2(alpha))

cos(alpha) = sqrt(1 - (11/12)^2)

cos(alpha) = sqrt(23/144)

Now we can substitute this value into the expression for sin(alpha - beta):

sin(alpha - beta) = (11/12)(15/17) - cos(alpha)(8/17)

sin(alpha - beta) = (11/12)(15/17) - sqrt(23/144)(8/17)

sin(alpha - beta) ≈ 0.210

Therefore, sin(alpha - beta) is approximately equal to 0.210.

User ScottOBot
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