Why is the derivative of a sine function a cosine function?
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Intuitive understanding of the derivatives of $\sin x$ and $\cos x$
5086
Why is the derivative of a circle's area its perimeter (and similarly for spheres)?
88854
Simple way to understand what derivative is
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Why are cosine and sine functions used when representing a signal or a wave?
120451
Why Does Snell's Law use Sine Instead of Angle Values?
82391
Why does $\sum_{k=1}^{\infty}\frac{{\sin(k)}}{k}={\frac{\pi-1}{2}}$?
131140
Understanding ProofWiki's proof of differentiation of sine power series
15155
Derivative of an even function is odd and vice versa
117583
Why does $\sum_{n=0}^\infty (\sin{\frac{1}{n}})(\sinh{\frac{1}{n}})(\cos n)$ converge
40235
How would I differentiate $\sin{x}^{\cos{x}}?$
56805
Why isn't the inverse of the function $x\mapsto x+\sin(x)$ expressible in terms of "the functions one finds on a calculator"?
155148
Why is $\sin 30^\circ=\frac{1}{2}$
82586
Why is cos -x equal to cos x?
123911
Why is the derivative of a vector orthogonal to the vector itself?
22916
Derivative of sigmoid function $\sigma (x) = \frac{1}{1+e^{-x}}$
97213
Why does $\sin(0)$ exist?
62522
Sine is algebraically less than cosine in given interval.