Evaluate: 1. tan 160°, cos 300° 2. sin 340°, cos 150° 3. sin 130°, sin(-70°), cos 350°

Mathematics
Evaluate: 1. tan 160°, cos 300° 2. sin 340°, cos 150° 3. sin 130°, sin(-70°), cos 350°

ScanSolve AI Answer

Right Triangle (opposite = 12, hypotenuse = 18)

Step 1: sinθ=oppositehypotenuse\sin \theta = \frac{opposite}{hypotenuse}.

Substitute: sinθ=1218\sin \theta = \frac{12}{18}.

Simplify:
sinθ=23\sin \theta = \frac{2}{3}

Step 2: Adjacent side = hypotenuse2opposite2\sqrt{hypotenuse^2 - opposite^2}.

Substitute: Adjacent side = 182122=324144=180\sqrt{18^2 - 12^2} = \sqrt{324 - 144} = \sqrt{180}.

Simplify:
180=36×5=65\sqrt{180} = \sqrt{36 \times 5} = 6\sqrt{5}

Step 3: cosθ=adjacenthypotenuse\cos \theta = \frac{adjacent}{hypotenuse}.

Substitute: cosθ=6518\cos \theta = \frac{6\sqrt{5}}{18}.

Simplify:
cosθ=53\cos \theta = \frac{\sqrt{5}}{3}

Step 4: tanθ=oppositeadjacent\tan \theta = \frac{opposite}{adjacent}.

Substitute: tanθ=1265\tan \theta = \frac{12}{6\sqrt{5}}.

Simplify:
tanθ=25=255\tan \theta = \frac{2}{\sqrt{5}} = \frac{2\sqrt{5}}{5}

Trigonometric Table (30°, 45°, 60°)

Using 30°-60°-90° triangle (sides opposite: 11, 3\sqrt{3}, hypotenuse 22).

Step 1: sin30=opp(30°)hyp\sin 30^\circ = \frac{opp (30°)}{hyp}.

Substitute: sin30=12\sin 30^\circ = \frac{1}{2}.

sin30=12\sin 30^\circ = \frac{1}{2}

cos30=adj(30°)hyp=32\cos 30^\circ = \frac{adj (30°)}{hyp} = \frac{\sqrt{3}}{2}.

cos30=32\cos 30^\circ = \frac{\sqrt{3}}{2}

tan30=opp(30°)adj(30°)=13=33\tan 30^\circ = \frac{opp (30°)}{adj (30°)} = \frac{1}{\sqrt{3}} = \frac{\sqrt{3}}{3}.

tan30=33\tan 30^\circ = \frac{\sqrt{3}}{3}

Step 2: sin60=opp(60°)hyp=32\sin 60^\circ = \frac{opp (60°)}{hyp} = \frac{\sqrt{3}}{2}.

sin60=32\sin 60^\circ = \frac{\sqrt{3}}{2}

cos60=adj(60°)hyp=12\cos 60^\circ = \frac{adj (60°)}{hyp} = \frac{1}{2}.

cos60=12\cos 60^\circ = \frac{1}{2}

tan60=opp(60°)adj(60°)=3\tan 60^\circ = \frac{opp (60°)}{adj (60°)} = \sqrt{3}.

tan60=3\tan 60^\circ = \sqrt{3}

Using 45°-45°-90° triangle (sides opposite: 11, 11, hypotenuse 2\sqrt{2}).

Step 3: sin45=opp(45°)hyp=12=22\sin 45^\circ = \frac{opp (45°)}{hyp} = \frac{1}{\sqrt{2}} = \frac{\sqrt{2}}{2}.

sin45=22\sin 45^\circ = \frac{\sqrt{2}}{2}

cos45=12=22\cos 45^\circ = \frac{1}{\sqrt{2}} = \frac{\sqrt{2}}{2}.

cos45=22\cos 45^\circ = \frac{\sqrt{2}}{2}

tan45=11=1\tan 45^\circ = \frac{1}{1} = 1.

tan45=1\tan 45^\circ = 1

\sin \theta = 2/3, \cos \theta = \sqrt{5/3, \tan \theta = 2\sqrt{5}/5

30°: \sin=1/2, \cos=\sqrt{3}/2, \tan=\sqrt{3}/3

45°: \sin=\sqrt{2}/2, \cos=\sqrt{2}/2, \tan=1

60°: \sin=\sqrt{3}/2, \cos=1/2, \tan=\sqrt{3}}

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