General Solution of an Equation

babybells96

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Find the general solution of this equation:3 tan x- (square root) 3 = 0. To start this problem, I added square root 3 from both sides and then divided body sides by 3, to get tan x = (square root) 3 over 3. I know that tangent is opposite over adjacent, thus, I know that the negative square root three must be across from theta. I do not think this problem is not a 30-60-90 or a 45-45-90 triangle, so I used the pyth theorem to solve for hypotenuse and got 3 square root 2. Now, I am not quite sure how to solve this problem. Thank you!
 
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Find the general solution of this equation:3 tan x- (square root) 3 = 0. To start this problem, I subtracted square root 3 from both sides and then divided body sides by 3, to get tan x = - (square root) 3 over 3. I know that tangent is opposite over adjacent, thus, I know that the negative square root three must be across from theta. I do not think this problem is not a 30-60-90 or a 45-45-90 triangle, so I used the pyth theorem to solve for hypotenuse and got 3 square root 2. Now, I am not quite sure how to solve this problem. Thank you!

Not quite.

3tanx3=0\displaystyle 3tanx-\sqrt{3}=0

 Now ADD3 to both sides:\displaystyle \ Now \ ADD \sqrt{3} \ to \ both \ sides:

3tanx=3\displaystyle 3tanx=\sqrt{3}

tanx=33\displaystyle tanx=\frac{\sqrt{3}}{3}

x=tan1(33)\displaystyle x=tan^{-1}(\frac{\sqrt{3}}{3})

x=π6\displaystyle x=\frac{\pi}{6}
 
Thank you so much for fixing my mistake and pointing me in the right direction. I did not understand that I needed to use the tangent inverse to get my answer. It makes sense now! Thank you.
 
π6\displaystyle \dfrac{\pi}{6} is a special angle for which you should know the values of the trig. functions there.

Since you asked for a general solution and tan(x+kπ)=tan(x)\displaystyle \tan(x+k\pi)=\tan(x) where kZ\displaystyle k\in\mathbb{Z}, then your general solution is:

x=π6+kπ=π6(6k+1)\displaystyle x=\dfrac{\pi}{6}+k\pi=\dfrac{\pi}{6}(6k+1)
 
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