promotion image of download ymail app
Promoted

sec (theta) = -5?

Solve for 0 <= (theta) < 360 :

sec (theta) = -5

[ In degrees ] Calculator okay.

Thanks for any help you can offer ^^

4 Answers

Relevance
  • Puggy
    Lv 7
    1 decade ago
    Favorite Answer

    sec(t) = -5

    First, let's express this as cosine. Note that sec(t) = 1/cos(t), so

    1/cos(t) = -5. Take the reciprocal of both sides, and we get

    cos(t) = -1/5

    -1/5 isn't any of our known values on the unit circle. For that reason,

    t = arccos(-1/5)

    This is one of our values, and it is in the second quadrant. We should have another value in our third quadrant. Our other solution would be 360 - arccos(-1/5), so

    t = {arccos(-1/5), 360 - arccos(-1/5)}

    Our approximate values are

    t ~= {101.54, 258.46}

    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    try:

    cos Θ = -1/5

    Θ= arccos (-1/5)

    • Commenter avatarLogin to reply the answers
  • 1 decade ago

    i will use x instead of theta:

    sec x = -5

    1 / cosx = -5 [now take recipriocals]

    cos x = -0.2

    x = 101.5, 258.5

    • Commenter avatarLogin to reply the answers
  • xeibeg
    Lv 5
    1 decade ago

    it is nearly 101.55 degree.

    • Commenter avatarLogin to reply the answers
Still have questions? Get your answers by asking now.