User:Temperal/sandbox

< User:Temperal
Revision as of 13:22, 14 August 2016 by Sp1729 (talk | contribs) (Problem 3)

Problem 1

Evaluate the following expressions:

(a) $\tan(45^\circ)$

(b) $\cos\left(\frac {7\pi}{4}\right)$

(c) $\sin\left(\frac {5\pi}{3}\right)$

(d) $\csc(135^\circ)$

(e) $\cot(945^\circ)$

(f) $\sin(\pi \sin(\pi/6))$

(g) $\tan(21\pi)$

(h) $\sec( - 585^\circ)$


Problem 2

Using the unit circle, find $\sin \left( x + \frac {\pi}{2} \right)$ and $\cos \left( x + \frac {\pi}{2} \right)$ in terms of $\sin x$ and $\cos x$.


Problem 3

In triangle $ABC$, $\angle B = 90^\circ$, $\sin A = 7/9$, and $BC = 21$. What is $AB$?

[hide]$12\sqrt{2}$[/hide]

Problem 4

What does the graph of $\sin 4x$ look like compared to the graphs of $\sin x$ and $\cos x$? What about the graph of $2\sin \left( 3x + \frac {\pi}{4} \right) - 1$?


Problem 5

Find the value of $\tan(\pi/12) \cdot \tan(2\pi/12) \cdot \tan(3\pi/12) \cdots \tan(5\pi/12).$



Problem 6

Suppose that parallelogram $ABCD$ has $\angle A = \angle C = 30^\circ$, $\angle B = \angle D = 150^\circ$, and the shorter diagonal $BD$ has length 2. If the height of the parallelogram is $a$, find the perimeter of $ABCD$ in terms of $a$.


Problem 7

Given a positive number $n$ and a number $c$ satisfying $- 1 < c < 1$, for how many values of $q$ with $0 \leq q < 2\pi$ is $\sin nq = c$? What if $c = 1$ or $c = - 1$?


Problem 8

How many solutions are there to the equation $\cos x = \frac {x^2}{1000}$, where $x$ is in radians?


Problem 9

Determine all $\theta$ such that $0 \le \theta \le \frac {\pi}{2}$ and $\sin^5\theta + \cos^5\theta = 1$.



Problem 10

Find the value of $\sin(15^\circ)$. Hint: Draw an isosceles triangle with vertex angle $30^\circ$.