Question

Write each of the following as a function of theta.
1.) sin(pi/4 - theta) 2.) tan(theta+30°)

Answer 1

Step-by-step explanation:

Let x represent theta.

$\sin( \frac{\pi}{4} - x )$

Using the angle addition trig formula,

$\sin(x - y) = \sin(x) \cos(y) - \cos(x) \sin(y)$

$\sin( \frac{\pi}{4} ) \cos(x) - \cos( \frac{\pi}{4} ) \sin(x)$

$( \frac{ \sqrt{2} }{2}) \cos(x) - (\frac{ \sqrt{2} }{2} )\sin(x)$

Multiply one side at a time

Replace theta with x , the answer is

$\frac{ \sqrt{2} \cos(x) }{2} - \frac{ \sin(x) \sqrt{2} }{2}$

2. Convert 30 degrees into radian

$\frac{30}{1} \times \frac{\pi}{180} = \frac{\pi}{6}$

Using tangent formula,

$\tan(x + y) = \frac{ \tan(x) + \tan(y) }{1 - \tan(x) \tan(y) }$

$\frac{ \tan(x) + \tan( \frac{\pi}{6} ) }{1 - \tan(x) \tan( \frac{\pi}{6} ) }$

Tan if pi/6 is sqr root of 3/3

$\frac{ \tan(x) + ( \frac{ \sqrt{3} }{3} ) }{1 - \tan(x) (\frac{ \sqrt{3} }{3} ) }$

Since my phone about to die if you later simplify that,

you'll get

$\frac{(3 \tan(x) + \sqrt{3} )(3 + \sqrt{3} \tan(x) }{3(3 - \tan {}^{2} (x) }$

Replace theta with X.