What is the least positive coterminal angle of (1490^\circ)?
Answer and explanation
Correct answer: \(50^\circ\)
Coterminal angles differ by an integral multiple of \(360^\circ\). Subtract the greatest suitable multiple of \(360^\circ\): \(1440^\circ=4\times360^\circ\). Thus, \(1490^\circ-1440^\circ=50^\circ\). Therefore, the least positive coterminal angle is \(50^\circ\). Although \(40^\circ\) is a close distractor, it does not differ from \(1490^\circ\) by a whole multiple of \(360^\circ\). Exam tip: divide the angle by \(360^\circ\) and take the positive remainder.
Frequently asked questions
What is the correct answer to this question?
\(50^\circ\)
Why is this the correct answer?
Coterminal angles differ by an integral multiple of \(360^\circ\). Subtract the greatest suitable multiple of \(360^\circ\): \(1440^\circ=4\times360^\circ\). Thus, \(1490^\circ-1440^\circ=50^\circ\). Therefore, the least positive coterminal angle is \(50^\circ\). Although \(40^\circ\) is a close distractor, it does not differ from \(1490^\circ\) by a whole multiple of \(360^\circ\). Exam tip: divide the angle by \(360^\circ\) and take the positive remainder.
Which subject and chapter does this question cover?
This is a Class 12 Mathematics question. Chapter: Trigonometric Functions. Topic: Angles.