trigonometry help please :(

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2) Simplify √-1-4/5-√-1

A.-1/24+19/24i
B.-21/26+1/26i
C.-19/24-1/24i
D.-1/26-21/26i

3) How many petals do the two rose curves r = 9 cos 61θ and r = 8 sin 60θ have combined?
A. 182
B. 242
C. 181
D. 131

4)What is true of the curve r = ƒ(θ) if its shape is unaffected when r is replaced by –r and θ is replaced by p – θ?
A. It's symmetric with respect to the x-axis.
B. It's symmetric with respect to the origin.
C. It's symmetric with respect to the line y = x.
D. It's symmetric with respect to the y-axis.


5) Simplify (√2-3i)^2
A.-5-6√2i
B.-7-6√2i
C. 2 − 9i
D.2 + 9i

Change 8 cis 240° to rectangular form.
A.-4-4√3i
B.-4√3-4i
C.-8√3-8i
D.-8-8√3i

  • trigonometry help please :( -

    √-1-4/5-√-1
    (-4+i)/(5-i)

    (-4+i)(5+i)
    ---------------
    (5-i)(5+i)

    (-21+i)/26

    so, (B)
    ***********************
    #3 - visit wolframalpha.com and see what the graphs look like if you have trouble algebraically.
    ***********************
    r ==> -r reflects through the origin
    θ ==> π-θ rotates 1/2 turn about the origin
    Looks like (B) to me
    ***************************
    (√2-3i)^2
    2-6√2i+9i^2
    ....
    *****************************
    cis240° = -cos60°-i sin60°
    ...

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