Formulas of Trigonometric and Logarithmic Functions

1)

$$Sinx = \frac{{{e^{ix}} - {e^{ - ix}}}}{{2i}}$$

2)

$$Cosx = \frac{{{e^{ix}} + {e^{ - ix}}}}{2}$$

3)

$$Tanx = \frac{{{e^{ix}} - {e^{ - ix}}}}{{i({e^{ix}} + {e^{ - ix}})}}$$

4)

$$Cotx = \frac{{i({e^{ix}} + {e^{ - ix}})}}{{{e^{ix}} - {e^{ - ix}}}}$$

5)

$$Secx = \frac{2}{{{e^{ix}} + {e^{ - ix}}}}$$

6)

$$Co\sec x = \frac{{2i}}{{{e^{ix}} - {e^{ - ix}}}}$$

7)

$$Log(x + iy) = Log\sqrt {{x^2} + {y^2}} + iTa{n^{ - 1}}\left( {\frac{y}{x}} \right)$$

8)

$$Log\left( {\frac{{x + iy}}{{x - iy}}} \right) = 2iTa{n^{ - 1}}\left( {\frac{y}{x}} \right)$$