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Find the values of x in [0,360) which satisfy 2cot^2x=-3cscx

User Jislam
by
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1 Answer

3 votes

Answer:

The values of x is -30 degrees and undefined

None of these values fall within the given range

Thus, no value within the given range is the solution to the equation

Explanation:

Here, we want to find the value of x that works for the equation in the selected range

2cot^2x = -3csc x

Mathematically, from trigonometry;

cot^2x = csc^2x - 1

Substitute this above

2(csc^2x - 1)= -3csc x

let csc x = b

2(b^2-1) = -3b

2b^2 - 2 + 3b = 0

2b^2 + 3b - 2 = 0

2b^2 + 4b - b - 2 = 0

2b(b+ 2) - 1( b + 2) = 0

(2b-1)(b + 2) = 0

2b = 1

b = -2

b = 1/2 = 0.5

or b = -2

Recall;

csc x = b

x = csc^-1 b

x = csc^-1 0.5

x = undefined

Secondly;

b = -2

x = csc^-1 (-2)

x = -30 degrees

As we can see , between the points

0 ≤ x < 360

None of our answers fall in these range

User McNab
by
7.5k points