Review | Differentiation Formulas
The definition of the derivative of $f$ is given by $$\frac{d}{dx}f(x)=f'(x)=\displaystyle\lim_{h\rightarrow 0 […]
もっと読む →Welcome to Math World!
The definition of the derivative of $f$ is given by $$\frac{d}{dx}f(x)=f'(x)=\displaystyle\lim_{h\rightarrow 0 […]
もっと読む →When $k>0$, the identity can be rewrite as $$\left(\begin{array}{c}n\\k\end{array}\right)=\frac{n}{k}\left(\be […]
もっと読む →Combinatorial Interpretation First, recall $\left(\begin{array}{c}n\\k\end{array}\right)$ is the number of pos […]
もっと読む →Combinatorial Interpretation First, recall $\left(\begin{array}{c}n\\k\end{array}\right)$ is the number of pos […]
もっと読む →Suppose that the constants $A$ and $B$ are given. Then, if we take the point $P(A,B)$ on the $xy$ plane, we ha […]
もっと読む →Product (to Sum) formulas To prove, we use the addition and subtraction formula： \begin{eqnarray*}\sin (A+ B)& […]
もっと読む →Proof of $\sin^{2}\frac{A}{2}=\frac{1-\cos A}{2}$ and $\cos^{2}\frac{A}{2}=\frac{1+\cos A}{2}$ We proof by usi […]
もっと読む →Proof by Addition Formulas If we Set $\beta=\alpha$ in Addition Formulas ： $ \sin (\alpha + \beta)=\sin \alpha […]
もっと読む →Consider any point $P(x,y)$ on $xy$ plane. Now, we let $r$ be the distance $|OP|$ and $\theta$ be the angle be […]
もっと読む →Let and be two vectors with the same initial point O. If H is the foot of the perpendicular from Y to the line […]
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