Answer :
You know that
[tex]\sin 0=0, \\ \cos 0=1[/tex].
Then it should be the sine function.
If [tex]y=-5 \sin x[/tex], then [tex]y(0)=-5 \sin 0=-5\cdot 0=0[/tex] and this function has amplitude 5, because [tex]y(\frac{3\pi}{2})=-5 \sin \frac{3\pi}{2}=-5\cdot (-1)=5[/tex].
If [tex]y=\sin (\pi x)[/tex], then [tex]y(\frac{1}{2})=\sin \frac{1}{2}\cdot \pi=\sin \frac{\pi}{2}=1 [/tex] and this function has amplitude 1.
Answer: Correct choice is B.
[tex]\sin 0=0, \\ \cos 0=1[/tex].
Then it should be the sine function.
If [tex]y=-5 \sin x[/tex], then [tex]y(0)=-5 \sin 0=-5\cdot 0=0[/tex] and this function has amplitude 5, because [tex]y(\frac{3\pi}{2})=-5 \sin \frac{3\pi}{2}=-5\cdot (-1)=5[/tex].
If [tex]y=\sin (\pi x)[/tex], then [tex]y(\frac{1}{2})=\sin \frac{1}{2}\cdot \pi=\sin \frac{\pi}{2}=1 [/tex] and this function has amplitude 1.
Answer: Correct choice is B.