How do you sketch y=3 - sin(x)?

1 Answer
Oct 14, 2015

graph{3-sinx [152.03, 188.41, -5.06, 13.14]}

You take test values of x and plot y accordingly. graph{3-sin(x) [97.46, 243, -32.36, 40.44]}

Explanation:

Most preferable values for x would be:-

0
45
60
90
120
135
180
270
360

So remember that
sin0=0
sin45=1/√2
sin60=√3/2
sin90=1
sin120=√3/4
sin135=1/√2
sin180=0
sin270=-1
sin360=0

So from 3, subtract these values and create a sketch. Plot the x-axis with just pi/2, pi and 2pi. (90, 180, and 360). You know which values like in between, so plot them with rough assumptions and join the lines. This graph would completely be above 0, in terms of y as if a minus value is attained for sinx, it's made into a positive value as 3 - (eg.sin270=-1) so, 3-(-1)=4.
In sketches only the shape of the graph and your workings matter, so compare the shape with the graph I've attached with this answer.