How many solutions does have in the interval , and what are they?
Answer and explanation
Correct answer: B. Two, and
- Step 1: has the reference angle , and sine is positive in quadrants I and II. Step 2. The solutions are and . **Answer: two solutions, and . Why not the others:** the others miss the second quadrant, use the third quadrant where sine is negative, or solve .
Practise more Mathematics A: Functions, Calculus, Complex Numbers and Probability.
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