Question

If the sin 0° = 0 then which statement is true

cos 90 = 1
cos 180 = 1
cos 90 = 0
cos 180 = 0

Answer 1

The correct statement is 'cos 90 = 0' because in the Cartesian coordinate system, orthogonal unit vectors have a scalar product of zero, and cos 90° corresponds to such a case.

Step-by-step explanation:

If sin 0° = 0, then we can determine the cosine of certain angles using fundamental trigonometric identities. Specifically, for the cosine function, we know that cos 90° = 0 when considering the unit circle and the definition of cosine. This is affirmed by the understanding that in the Cartesian coordinate system, the scalar products of unit vectors that are orthogonal to each other are zero, which is the case for the axes at 90 degrees. Thus, among the given options, the statement cos 90 = 0 is true. On the other hand, cos 180° = -1, which is not an option provided.

Answer 2

Step-by-step explanation:

If the sin 0° = 0, then which statement is true?

1) cos 90° = 0, because the cosine and sine are complements

2) cos 180° = 1, because the cosine and sine are supplements

3) cos 90° = 1, because the cosine and sine are complements

4) cos 180° = 0, because the cosine and sine are supplementscc