What is the domain of a trig function with y = 2sin(x)?

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so_gr_lo
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Homework Statement
I am supposed to find the limits of a trig function, which I have managed to do, but I don’t know how to show that the range can be achieved within the given domain.
Relevant Equations
y = 2sin(x)
y = 2sin(x)

-1≤ sin(x) ≤ 1

-2 ≤ 2sin(x) ≤ 2

so -2 and 2 are the max/min limits

but the domain is -π < x ≤ π

Do I find the values of x that outputs -2 and 2 and show that they are within the domain ?
 
on Phys.org
2sin x has period ##2\pi## so both the minimum and the maximum value are realized in the domain. Draw the graph.
 
so_gr_lo said:
Do I find the values of x that outputs -2 and 2 and show that they are within the domain ?
That is a good approach. Then use the continuity of the function to say that it covers everything in between.
 
yeah I think that might be what is expected, thanks