What is the coterminal angle of (840^\circ) between (0^\circ) and (360^\circ)?
Answer and explanation
Correct answer: \(120^\circ\)
Coterminal angles differ by an integral multiple of \(360^\circ\). Since \(840^\circ-2\times360^\circ=120^\circ\), the coterminal angle lying between \(0^\circ\) and \(360^\circ\) is \(120^\circ\). Although \(90^\circ\) may seem close, \(840^\circ-90^\circ=750^\circ\), which is not a multiple of \(360^\circ\). Exam tip: add or subtract multiples of \(360^\circ\) to bring an angle into the required interval.
Frequently asked questions
What is the correct answer to this question?
\(120^\circ\)
Why is this the correct answer?
Coterminal angles differ by an integral multiple of \(360^\circ\). Since \(840^\circ-2\times360^\circ=120^\circ\), the coterminal angle lying between \(0^\circ\) and \(360^\circ\) is \(120^\circ\). Although \(90^\circ\) may seem close, \(840^\circ-90^\circ=750^\circ\), which is not a multiple of \(360^\circ\). Exam tip: add or subtract multiples of \(360^\circ\) to bring an angle into the required interval.
Which subject and chapter does this question cover?
This is a Class 12 Mathematics question. Chapter: Trigonometric Functions. Topic: Angles.
