Home » If angle (theta) is 135o, evaluate cos(theta)

If angle (theta) is 135o, evaluate cos(theta)

If angle (theta) is 135o, evaluate cos(theta)

  • A.
    (frac{1}{2})
  • B.
    (frac{sqrt{2}}{2})
  • C.
    (-frac{sqrt{2}}{2})
  • D.
    (-frac{1}{2})
Correct Answer: Option C
Explanation

(theta) = 135o
Cos 135o = Cos(90 + 45)o
= cos90ocos45o – sin90osin45o
= 0cos45o – (1 x (frac{sqrt{2}}{2}))
= (-frac{sqrt{2}}{2})

There is an explanation video available below.

Explanation Video

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