HELP! BRAINLIEST! Which of the following represents vector w = 11i − 60j in trigonometric form? w = 61❬sin 280.

HELP! BRAINLIEST!
Which of the following represents vector w = 11i − 60j in trigonometric form?

w = 61❬sin 280.389°, cos 280.389°❭
w = 61❬cos 280.389°, sin 280.389°❭
w = 61❬cos 79.611°, sin 79.611°❭
w = 61❬sin 79.611°, cos 79.611°❭

1 thought on “HELP! BRAINLIEST! Which of the following represents vector w = 11i − 60j in trigonometric form? w = 61❬sin 280.”

  1. Answer:
      w = 61❬cos 280.389°, sin 280.389°❭
    Step-by-step explanation:
    The “trigonometric form” of a vector is …
      (magnitude)❬cos(angle), sin(angle)❭
    This is sometimes abbreviated …
      magnitude cis(angle)
    __
    This form immediately eliminates choices A and D, as those have the trig functions reversed. The signs on the unit vectors i and j tell you the vector has a 4th-quadrant angle, so will be between 270° and 360°. Only answer choice B makes any sense.
      w = 61❬cos 280.389°, sin 280.389°❭
    _____
    Additional comment
    The angle is computed from …
      θ = arctan(y/x) = arctan(-60/11) = -79.611°
    Expressed as a positive angle in the range [0, 360°), that will be …
      360° +(-79.611°) = 280.389°
    __
    The abbreviation “cis” is mentioned as an aid to remembering the (x, y) coordinates are the cosine and sine of the angle, in that order.

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