Express the following in terms of (positive) acute angles: - $\sin240^{\circ}$
- $\cos(-50^{\circ})$
- $\tan600^{\circ}$
- $-\sin120^{\circ}$
- $\cos50^{\circ}$
- $\tan60^{\circ}$
Write the following in terms of $\sin\theta$, $\cos\theta$, or $\tan\theta$ only: - $\sin(180^{\circ}-\theta)$
- $\cos(\theta-540^{\circ})$
- $\tan(540^{\circ}-\theta)$
- $\sin\theta$
- $-\cos\theta$
- $-\tan\theta$
Find the exact values of: - $\cos495^{\circ}$
- $\tan(-225^{\circ})$
- $\sin(-60^{\circ})$
- $-\dfrac{\sqrt{2}}{2}$
- $-1$
- $-\dfrac{\sqrt{3}}{2}$
Simplify: - $1-\cos^2\frac{1}{2}\theta$
- $5\sin^23\theta+5\cos^23\theta$
- $\sin^2\frac{1}{2}\theta$
- $5$
Simplify: - $(1+\sin x)^2+(1-\sin x)^2+2\cos^2x$
- $\sin^4\theta+\sin^2\theta\cos^2\theta$
Prove the following identities: - $(\sin\theta+\cos\theta)^2\equiv2\sin\theta\cos\theta + 1$
- $\dfrac{1}{\cos\theta}-\cos\theta\equiv\sin\theta\tan\theta$
See video
Prove the following identities: - $(2\sin\theta-\cos\theta)^2+(\sin\theta+2\cos\theta)^2\equiv5$
- $\sin^2x\cos^2y-\cos^2x\sin^2y\equiv\sin^2x-\sin^2y$
See video
Given $\tan\theta=\dfrac{5}{12}$ and $\theta$ is acute, find the exact value of: - $\sin\theta$
- $\cos\theta$
- $\dfrac{5}{13}$
- $\dfrac{12}{13}$
Given $\cos\theta=-\dfrac{3}{5}$ and $\theta$ is obtuse, find the exact value of: - $\sin\theta$
- $\tan\theta$
- $\dfrac{4}{5}$
- $-\dfrac{4}{3}$
Given $\sin\theta=-\dfrac{7}{25}$ and $270^{\circ}<\theta<360^{\circ}$, find the exact value of: - $\cos\theta$
- $\tan\theta$
- $\dfrac{24}{25}$
- $-\dfrac{7}{24}$
For the following pair of equations, find a single equation in terms of $x$ and $y$, but not $\theta$: $$x=\sin\theta \quad y=\cos^2\theta$$
$x^2+y=1$
For the following pair of equations, find a single equation in terms of $x$ and $y$, but not $\theta$: $$x=\sin\theta+\cos\theta \quad y=\cos\theta-\sin\theta$$
$x^2+y^2=2$
Find the angle marked $x$ in the following triangle.
$79.9^{\circ}$
By first finding $x$, find the area of the following triangle.
$63.2$
By first finding $x$, find the area of the following triangle.
$258$
Find the reflex angle marked $x$ in the following triangle.
$302^{\circ}$
Calculate the area of a triangle with side lengths $10$, $13$, and $18$.
$63.5$
Find the area of the quadrilateral $ABCD$.
$25.6$