A. To evaluate sin 103°, we first need to determine which quadrant 103° is in. Since 90° < 103° < 180°, we know it is in the second quadrant. In that quadrant, sine is positive, so we know the answer will be positive.
We can use the sine function on our calculator or reference sheet to find that sin 103° = 0.973.
B. To evaluate cos 113°, we first need to determine which quadrant 113° is in. Since 90° < 113° < 180°, we know it is in the second quadrant. In that quadrant, cosine is negative, so we know the answer will be negative.
We can use the cosine function on our calculator or reference sheet to find that cos 113° = -0.321.
C. To evaluate sin 136°, we first need to determine which quadrant 136° is in. Since 90° < 136° < 180°, we know it is in the second quadrant. In that quadrant, sine is positive, so we know the answer will be positive.
We can use the sine function on our calculator or reference sheet to find that sin 136° = 0.469.
D. To evaluate cos 157°, we first need to determine which quadrant 157° is in. Since 90° < 157° < 180°, we know it is in the second quadrant. In that quadrant, cosine is negative, so we know the answer will be negative.
We can use the cosine function on our calculator or reference sheet to find that cos 157° = -0.985.
Trigonometry ratio. Evaluate the following and show your workings. A. sin 103° B.cos 113° C.sin 136° D.cos 157°
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