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If sin θ = a and cos θ = b, represent each of the following in terms of a and b.
a. csc(θ) + sec(-θ)
b. cot θ - csc θ

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Answer:

Explanation:

a. csc(θ) + sec(-θ)

Recall that csc(θ) = 1/sin(θ) and sec(θ) = 1/cos(θ). Also note that sec(-θ) = sec(θ), since the secant function is even.

Therefore,

csc(θ) + sec(-θ) = 1/sin(θ) + 1/cos(θ)

Substituting a for sin(θ) and b for cos(θ), we get:

csc(θ) + sec(-θ) = 1/a + 1/b

To simplify this expression, we can find a common denominator:

csc(θ) + sec(-θ) = (b + a)/(ab)

Therefore, csc(θ) + sec(-θ) = (a + b)/(ab)

b. cot θ - csc θ

Recall that cot(θ) = cos(θ)/sin(θ) and csc(θ) = 1/sin(θ).

Therefore,

cot(θ) - csc(θ) = cos(θ)/sin(θ) - 1/sin(θ)

Substituting a for sin(θ) and b for cos(θ), we get:

cot(θ) - csc(θ) = b/a - 1/a

To simplify this expression, we can find a common denominator:

cot(θ) - csc(θ) = (b - 1)/a

Therefore, cot(θ) - csc(θ) = (b - 1)/a.

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