Question

The cosine of an angle is the ratio of the opposite side over the hypotenuse.

Answer 1

Answer:

False, The cosine of an angle is the ratio of the opposite side over the hypotenuse.

Let ΔABC is a right angled triangle, ∠C = 90°

Figure is attached.

let ∠B be $\theta$

Then the trigonometric ratios are the following:

$sin\,\theta=\frac{AC}{AB}$

$cos\,\theta=\frac{CB}{AB}$

$tan\,\theta=\frac{AC}{CB}$

$cosec\,\theta=\frac{AB}{AC}$

$sec\,\theta=\frac{AB}{CB}$

$tan\,\theta=\frac{CB}{AC}$

So, clearly $cos\,\theta=\frac{Adjacent}{Hypotenuse}$

Its $sin\,\theta=\frac{Opposite}{Hypotenuse}$

Answer 2

It's False.Sine is a trigonometric function of the angle in a right triangle is equal to the ratio of the opposite leg to the angle of the hypotenuse.