gpt-4: Actually, the value of \(\sin(-\pi/2)\) is indeed \(-1\). The sine function represents the y-coordinate of a point on the unit circle corresponding to a given angle. At \(-\pi/2\) radians, which is equivalent to 270 degrees or a quarter circle in the negative direction, the point on the unit circle is at the bottom with coordinates (0, -1). Therefore, the sine of \(-\pi/2\) is \(-1\).

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The smarter it is, the more conviction it has. GPT-3.5 has a lot of impostor syndrome and it's probably deserved lol. But GPT-4 starts to stutter when you give it enough math questions, which aren't its forte.