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Find the following trigonometric values. Express answers exactly. cos(240∘)= sin(240∘)=

User Tha Leang
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Final answer:

The exact values for cos(240°) and sin(240°) are -1/2 and -√3/2, respectively. These values are derived using the unit circle and the fact that 240° is in the third quadrant where both sine and cosine are negative.

Step-by-step explanation:

To find the values of cos(240°) and sin(240°), we can use the unit circle where the angle is measured from the positive x-axis. The angle of 240° places us in the third quadrant where both sine and cosine values are negative.

cos(240°) = cos(180° + 60°) = -cos(60°) = -½

sin(240°) = sin(180° + 60°) = -sin(60°) = -√3/2

Thus, the exact values are:

  • cos(240°) = -½
  • sin(240°) = -√3/2

User Malcolm Crum
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