JAMB - Mathematics (1981 - No. 2)
If sine x equals cosine x, what is x in radians?
\(\frac{\pi}{2}\)
\(\frac{\pi}{3}\)
\(\frac{\pi}{4}\)
\(\frac{\pi}{6}\)
\(\frac{\pi}{12}\)
解释
\(\sin x = \cos x\)
\(\implies x = 45°\)
In radians, \(x = \frac{\pi}{4}\).