Can someone help me with these questions?

Question

anonymous · Answer

attachment

mathmale · Answer

What do you need to know to answer #1 (3.png)?
What have you been able to do so far?
Can you distinguish between the graphs of the sine function and the cosine function?   How?

anonymous · Answer

No I don't know how to distinguish them, I'm trying to get ahead because I won't be able to any of my work for some time due to health reasons

anonymous · Answer

@mathmale

anonymous · Answer

Sine graphs always begin at the origin

mathmale · Answer

As Ayato says, "Sine graphs always begin at the origin."  This is correct if there is no vertical offset to the graph.
So, if x=0, y=sin x=sin 0 = 0.
      If x=0, y=cos x =cos 0 = ??    (important that you know this.)

jiteshmeghwal9 · Answer

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