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Taylor Series of $arctan(x)$

$$ \begin{aligned} arctan^{(1)}(x) & = {d \over dx} \left( arctan(x) \right) = {1 \over {1 + x^2}}\\ arctan^{(2)}(x) & = {d \over dx} \left( {1 \over {1 + x^2}} \right) = {{-2x} \over {(1 + x^2)^2}}\\ arctan^{(3)}(x) & = {d \over dx} \left( {{2x} \over {(1 + x^2)^2}} \right) = {{8x^2} \over {(1 + x^2)^3}} - {{2} \over {(1 + x^2)^2}}\\ arctan^{(4)}(x) & = {d \over dx} \left( {{8x^2} \over {(1 + x^2)^3}} - {{2} \over {(1 + x^2)^2}} \right) = {{-48x^3} \over {(1 + x^2)^4}} + {{24x} \over {(1 + x^2)^3}}\\ arctan^{(5)}(x) & = {d \over dx} \left( {{-48x^3} \over {(1 + x^2)^4}} + {{24x} \over {(1 + x^2)^3}} \right) = {{384x^4} \over {(1 + x^2)^5}} - {{288x^2} \over {(1 + x^2)^4}} - {24 \over {(1+x^2)^3}} \\ arctan^{(6)}(x) & = {d \over dx} \left( {{384x^4} \over {(1 + x^2)^5}} - {{288x^2} \over {(1 + x^2)^4}} - {24 \over {(1+x^2)^3}} \right) = {{-3840x^5} \over {(1 + x^2)^6}} + {{3840x^3} \over {(1 + x^2)^5}} - {720x \over {(1+x^2)^4}} \\ arctan^{(7)}(x) & = {d \over dx} \left( {{-3840x^5} \over {(1 + x^2)^6}} + {{3840x^3} \over {(1 + x^2)^5}} - {720x \over {(1+x^2)^4}} \right) = {{46080x^6} \over {(1 + x^2)^7}} - {{57600x^4} \over {(1 + x^2)^6}} + {17280x^2 \over {(1+x^2)^5}}- {720 \over {(1+x^2)^4}} \\ \end{aligned} $$
We can now determine the values of these derivatives at 0:
$$ \begin{aligned} arctan^{(0)}(0) & = 0\\ arctan^{(1)}(0) & = 1\\ arctan^{(2)}(0) & = 0\\ arctan^{(3)}(0) & = -2!\\ arctan^{(4)}(0) & = 0\\ arctan^{(5)}(0) & = 4!\\ arctan^{(6)}(0) & = 0\\ arctan^{(7)}(0) & = -6!\\ arctan^{(8)}(0) & = 0\\ arctan^{(9)}(0) & = 8!\\ arctan^{(n)}(0) & = (n-1)! \,\mbox{where n is uneven}\\ arctan(x) & = 0 + 1 \cdot x + 0 \cdot {{x^2} \over 2!} - 2! \cdot {{x^3} \over 3!} + 0 \cdot {{x^4} \over 4!} + 4! \cdot {{x^5} \over 5!}+ 0 \cdot {{x^6} \over 6!} - 6! \cdot {{x^7} \over 7!} + 0 \cdot {{x^8} \over 8!} + 8! \cdot {{x^9} \over 9!} + ....\\ & = x - {{x^3} \over 3} + {{x^5} \over 5} - {{x^7} \over 7} + {{x^9} \over 9} + ....\\ & = \sum_{j=0}^\infty (-1)^j {x^{2j+1} \over {2j+1}} \end{aligned} $$
One can use this now also to determine the value of $\pi$
$$ \begin{aligned} tan({\pi \over 4}) & = 1\\ \therefore \, arctan(1) & = {\pi \over 4}\\ \pi & = 4 \cdot arctan(1) \\ & = 4 \cdot \left( 1 - {1 \over 3} + {1 \over 5} - {1 \over 7} + {1 \over 9} - ... \right) \end{aligned} $$
This is however converging very slowly and there are other ways of speeding them up (please have a look at Calculating $\pi$ also on this site)

Taylor Series of $arcsin(x)$ and $arccos(x)$

These are a bit more involved.
$$ \begin{aligned} arcsin^{(1)}(x) & = {1 \over \sqrt{1-x^2}}\\ arcsin^{(2)}(x) & = {x \over \left( \sqrt{1-x^2} \right)^3}\\ arcsin^{(3)}(x) & = {1 \over \left( \sqrt{1-x^2} \right)^3} + {{3x^2} \over \left( \sqrt{1-x^2} \right)^5}\\ arcsin^{(4)}(x) & ={{9x} \over \left( \sqrt{1-x^2} \right)^5} + {{15x^3} \over \left( \sqrt{1-x^2} \right)^7}\\ arcsin^{(5)}(x) & ={{9} \over \left( \sqrt{1-x^2} \right)^5} + {{90x^2} \over \left( \sqrt{1-x^2} \right)^7}+ {{105x^4} \over \left( \sqrt{1-x^2} \right)^9}\\ arcsin^{(6)}(x) & ={{225x} \over \left( \sqrt{1-x^2} \right)^7} + {{1050x^3} \over \left( \sqrt{1-x^2} \right)^9}+ {{945x^5} \over \left( \sqrt{1-x^2} \right)^{11}}\\ arcsin^{(7)}(x) & ={{225} \over \left( \sqrt{1-x^2} \right)^7} + {{4725x^2} \over \left( \sqrt{1-x^2} \right)^9}+ {{14175x^4} \over \left( \sqrt{1-x^2} \right)^{11}}+ {{10395x^6} \over \left( \sqrt{1-x^2} \right)^{13}}\\ arcsin^{(8)}(x) & ={{11025x} \over \left( \sqrt{1-x^2} \right)^9} + {{99225x^3} \over \left( \sqrt{1-x^2} \right)^{11}}+ {{218295x^5} \over \left( \sqrt{1-x^2} \right)^{13}}+ {{135135x^7} \over \left( \sqrt{1-x^2} \right)^{15}}\\ arcsin^{(9)}(x) & = {{11025} \over \left( \sqrt{1-x^2} \right)^9} + {{396900x^2} \over \left( \sqrt{1-x^2} \right)^{11}}+ {{2182950x^4} \over \left( \sqrt{1-x^2} \right)^{13}}+ {{3783780x^6} \over \left( \sqrt{1-x^2} \right)^{15}}+ {{2027025x^8} \over \left( \sqrt{1-x^2} \right)^{17}}\\ \end{aligned} $$
Let's look at the values at zero:
$$ \begin{aligned} arcsin(0) & = 0\\ arcsin^{(1)}(0) & = {1 \over \sqrt{1-0^2}}\\ & = 1\\ arcsin^{(2)}(0) & = {0 \over \left( \sqrt{1-0^2} \right)^3}\\ & = 0\\ arcsin^{(3)}(0) & = {1 \over \left( \sqrt{1-0^2} \right)^3} + {{3 \cdot 0^2} \over \left( \sqrt{1-0^2} \right)^5}\\ & = 1\\ arcsin^{(4)}(0) & ={{9 \cdot 0} \over \left( \sqrt{1-0^2} \right)^5} + {{15 \cdot 0^3} \over \left( \sqrt{1-0^2} \right)^7}\\ & = 0\\ arcsin^{(5)}(0) & ={{9} \over \left( \sqrt{1-0^2} \right)^5} + {{90 \cdot 0^2} \over \left( \sqrt{1-0^2} \right)^7}+ {{105 \cdot 0^4} \over \left( \sqrt{1-0^2} \right)^9}\\ & = 9\\ arcsin^{(6)}(0) & ={{225 \cdot 0} \over \left( \sqrt{1-0^2} \right)^7} + {{1050 \cdot 0^3} \over \left( \sqrt{1-0^2} \right)^9}+ {{945 \cdot 0^5} \over \left( \sqrt{1-0^2} \right)^{11}}\\ & = 0\\ arcsin^{(7)}(0) & ={{225} \over \left( \sqrt{1-0^2} \right)^7} + {{4725 \cdot 0^2} \over \left( \sqrt{1-0^2} \right)^9}+ {{14175 \cdot 0^4} \over \left( \sqrt{1-0^2} \right)^{11}}+ {{10395 \cdot 0^6} \over \left( \sqrt{1-0^2} \right)^{13}}\\ & = 225\\ arcsin^{(8)}(0) & ={{11025 \cdot 0} \over \left( \sqrt{1-0^2} \right)^9} + {{99225 \cdot 0^3} \over \left( \sqrt{1-0^2} \right)^{11}}+ {{218295 \cdot 0^5} \over \left( \sqrt{1-0^2} \right)^{13}}+ {{135135 \cdot 0^7} \over \left( \sqrt{1-0^2} \right)^{15}}\\ & = 0\\ arcsin^{(9)}(0) & = {{11025} \over \left( \sqrt{1-0^2} \right)^9} + {{396900 \cdot ^2} \over \left( \sqrt{1-0^2} \right)^{11}}+ {{2182950 \cdot 0^4} \over \left( \sqrt{1-0^2} \right)^{13}}+ {{3783780 \cdot 0^6} \over \left( \sqrt{1-0^2} \right)^{15}}+ {{2027025 \cdot 0^8} \over \left( \sqrt{1-0^2} \right)^{17}}\\ & = 11025\\ \end{aligned} $$
We can substitute this in the Taylor expansion:
$$ \begin{aligned} arcsin(x) & = 0 + 1 \cdot x + 0 \cdot {{x^2} \over 2!} + 1 \cdot {{x^3} \over 3!} + 0 \cdot {{x^4} \over 4!} + 9 \cdot {{x^5} \over 5!} + 0 \cdot {{x^6} \over 6!} + 225 \cdot {{x^7} \over 7!} + 0 \cdot {{x^8} \over 8!} + 11025 \cdot {{x^9} \over 9!} +....\\ & = x + {{x^3} \over 3!} + 9 \cdot {{x^5} \over 5!} + 225 \cdot {{x^7} \over 7!} + 11025 \cdot {{x^9} \over 9!} +....\\ \end{aligned} $$
This can be reduced to a sigma format of which the steps are not shown here:
$$ \begin{aligned} arcsin(x) & = \sum_{j=0}^\infty {{(2j)!} \over {4^j (j!)^2 (2j+1)}}x^{2j+1} \end{aligned} $$