Question

10) Given sin 0 = 0.259 and tan 0 = -0.268,

determine cos 0. Keep your answer rounded
to four decimal places.
ERIES
S
TU
A) cos 0 = -0.9664
REST
B) cos 0 = 0.9664
TERET
C) cos 0 = -0.9700
D) cos 0 = 0.9700

Answer 1

(A) cos
`\theta` = -0.9664

`cos \theta =-0.9659`

Explanation:

Given

`sin \theta = 0.259 \:and;\\ tan \theta = -0.268`

Sine is Positive and Tangent is Negative in Quadrant II.

In Quadrant II, Cosine is also Negative.

`sin \theta = 0.259 \\\theta=arcsin 0.259=15.01^\circ\\$Therefore in Quadrant II:\\cos \theta =-cos\:15.01^\circ =-0.9659`

Closest Option is A.