Math Analysis:
Find all values of x between 0 degrees and 360 degrees that satisfy the equation. Round the approximate answers to the nearest tenth of a degree.
3. 3cot^2x -1 = 0
4. 2cos^2x + 9cosx + 4 = 0

Question

Math Analysis:
Find all values of x between 0 degrees and 360 degrees that satisfy the equation. Round the approximate answers to the nearest tenth of a degree.
3. 3cot^2x -1 = 0
4. 2cos^2x + 9cosx + 4 = 0

anonymous · Answer

so i use the formula for tan2x?

anonymous · Answer

it's cot^2 x

anonymous · Answer

$$\cot ^{2} x $$

kropot72 · Answer

Good. Sorry for my error. Lets start again.

anonymous · Answer

$$3\cot ^{2}x - 1 = 0$$

anonymous · Answer

$$2\cos ^{2}x + 9\cos + 4 = 0$$

kropot72 · Answer

Factorising:
$$3\cot ^{2}x-1=(\sqrt{3}\cot x+1)(\sqrt{3}\cot x-1)$$=0
$$\sqrt{3}\cot x=1$$
$$\sqrt{3}\cot x=-1$$
Can you find x for both roots ?
Hint:$$\cot x=\frac{1}{\tan x}$$

anonymous · Answer

why did you put a square root on the 3?

kropot72 · Answer

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