# How do you graph y = -2tan(x+(pi/4))?

Nov 15, 2016

graph{ -2tan(x+(pi/4)) [-10, 10, -5, 5]}

Required graph.

#### Explanation:

For the graphing questions, I always follow this way which is quite easy.

Firstly, Look at the trigonometric function which in this case is $\tan$. You need to know the graph of $y = \tan x$. graph{tanx [-8.89, 8.89, -4.444, 4.445]}

Secondly, for the period of the function, look for the coefficient of $x$ which in this case is 1. So the period of this graph is same as that of $y = \tan x$.

Thirdly, In $\left(x + \left(\frac{\pi}{4}\right)\right)$ , if there is use of + sign, it means shifting the whole graph left. If there is - sign, then we have to shift the whole graph right. In this case, we have to shift it left.

graph{tan(x+(pi/4)) [-8.89, 8.89, -4.444, 4.445]}

Now,
Look for the coefficient of the trigonometric function which in this case is 2. So, if $\tan \left(\frac{\pi}{4}\right)$ gives $y$= 1, then 2$\tan \left(\frac{\pi}{4}\right)$ gives $y$= 2. Multiply every outcomes by 2. You do not have to do it for every $y$ but some just to know the shape.
graph{2tan(x+(pi/4)) [-8.89, 8.89, -4.444, 4.445]}

Lastly, the minus sign will rotate the graph via x-axis. X-axis would act as the mirror.
graph {-2tan(x+(pi/4)) [-8.89, 8.89, -4.444, 4.445]}