Trigonometry (circular functions)
Hi everyone i need help with this badly. I'm hopeless at math and can't seem to figure these questions out. It is for my pre engineering course it is pretty easy stuff but i study by correspondence and teach myself so any help would be very much appreciated!
1A) Given cos A=0.2 and sin A=0.98
a) sin(180degrees + A)
b) cos(360degrees - A)
c) tan(180degrees + A)
d) cos(180degrees - A)
e) sin(360degrees + A)
2) Sketch the graph of y= 15 sin 2x for 0<x<360?
3)Draw the graph of y=120cos(6theta-45degrees)?
- what is the amplitude?
- the period?
- the phase shift?
4)Given that sin 55degrees = 0.819 and cos20degrees = 0.94,
show how you would use the identities for sin(A(plus or minus)B) and cos(A(plus or minus)B) to find the following:
a) sin 75degrees
b) cos 35 degrees
c) tan 35 degrees
Showing the steps you would follow. NOTE: sin^2theta+cos^2theta=1