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If cos x = √a/b, find cosce x​

User Tom Finet
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1 Answer

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Answer: csc(x) = (√b) / √(b(b - a))

Explanation:

To find the cosecant (csc) of an angle x when you know the cosine (cos) of that angle, you can use the following trigonometric identity:

csc(x) = 1 / sin(x)

First, you need to find the sine (sin) of x. Since you know that cos(x) = √(a/b), you can use the Pythagorean identity to find sin(x):

sin(x) = √(1 - cos^2(x))

sin(x) = √(1 - (√(a/b))^2)

sin(x) = √(1 - a/b)

sin(x) = √((b - a) / b)

Now that you have sin(x), you can find csc(x):

csc(x) = 1 / sin(x)

csc(x) = 1 / (√((b - a) / b))

To rationalize the denominator, you can multiply both the numerator and denominator by √b:

csc(x) = (√b) / (√b * √((b - a) / b))

csc(x) = (√b) / √(b(b - a))

So, the cosecant of x is:

csc(x) = (√b) / √(b(b - a))

This is the expression for the cosecant of x in terms of a and b when the cosine of x is √a/b.

User Rohan Bhatia
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