Question

@agent0smith Could you help me with a trigonometry question please?

Answer 1

@mathmate @skullpatrol

Answer 2

@zepdrix

Answer 3

@paki

Answer 4

The given answer is correct. This is how it works.
\(y=a\sin(bx)\)
means that a is the vertical stretch factor.
a>0 stretches the graph vertically by a factor of a with respect to the x-axis..
(note, if |a|>1, the graph actually stretches, if |a|<1, the graph shortens vertically)
if a<0, then a reflection about the x-axis is performed after the stretching.

b is a horizontal contraction factor.
if |b|>0, the graph contracts horizontally by a factor of b with respect to the y-axis..
This means that when |b|<1, the graph expands horizontally.
Again, if b<0, it will contract and reflect about the y-axis.