Explore: Find Cos

sin ⁡ α cos ⁡ β cos ⁡ γ cos ⁡ ( 2 α ) + cos ⁡ ( 2 β ) + cos ⁡ ( 2 γ ) = − 4 cos ⁡ α cos ⁡ β cos ⁡ γ − 1 − cos ⁡ ( 2 α ) + cos ⁡ ( 2 β ) + cos ⁡ ( 2 γ

formula cos ⁡ ( x − y ) = cos ⁡ x cos ⁡ y + sin ⁡ x sin ⁡ y {\displaystyle \cos(x-y)=\cos x\cos y+\sin x\sin y\,} and the added condition 0 < x cos ⁡ x <

hold: cos ⁡ a = cos ⁡ b cos ⁡ c + sin ⁡ b sin ⁡ c cos ⁡ A cos ⁡ A = − cos ⁡ B cos ⁡ C + sin ⁡ B sin ⁡ C cos ⁡ a cos ⁡ a = cos ⁡ A + cos ⁡ B cos ⁡ C sin

n 1 cos ⁡ θ i − n 2 cos ⁡ θ t n 1 cos ⁡ θ i + n 2 cos ⁡ θ t , t s = 2 n 1 cos ⁡ θ i n 1 cos ⁡ θ i + n 2 cos ⁡ θ t , r p = n 2 cos ⁡ θ i − n 1 cos ⁡ θ

the matrix R = [ cos ⁡ θ − sin ⁡ θ sin ⁡ θ cos ⁡ θ ] {\displaystyle R={\begin{bmatrix}\cos \theta &-\sin \theta \\\sin \theta &\cos \theta \end{bmatrix}}}

are denoted as sin ⁡ ( θ ) {\displaystyle \sin(\theta )} and cos ⁡ ( θ ) {\displaystyle \cos(\theta )} . The definitions of sine and cosine have been extended

x = cos ⁡ x + i sin ⁡ x , {\displaystyle e^{ix}=\cos x+i\sin x,} where e is the base of the natural logarithm, i is the imaginary unit, and cos and sin

it is the case that ( cos ⁡ x + i sin ⁡ x ) n = cos ⁡ n x + i sin ⁡ n x , {\displaystyle {\big (}\cos x+i\sin x{\big )}^{n}=\cos nx+i\sin nx,} where i

{\partial }{\partial r}}+{\frac {1}{r}}\cos \varphi {\frac {\partial }{\partial \varphi }}.\end{aligned}}} To find the Cartesian slope of the tangent line

:= n -> product(i, i = 1..n); Find ∫ cos ⁡ ( x a ) d x {\displaystyle \int \cos \left({\frac {x}{a}}\right)dx} . int(cos(x/a), x); Output: a sin ⁡ ( x