cos(2/5*pi)+i*sen(2/5*pi)=
You asked:
Evaluate the expression: \(\cos\left( \frac{2}{5} \cdot \pi \right) + i \cdot \sin\left( \frac{2}{5} \cdot \pi \right)\)
MathBot Answer:
\[\cos\left( \frac{2}{5} \cdot \pi \right) + i \cdot \sin\left( \frac{2}{5} \cdot \pi \right) = - \frac{1}{4} + \frac{\sqrt{5}}{4} + i \sqrt{\frac{\sqrt{5}}{8} + \frac{5}{8}}\]
\(i\) is the imaginary unit, defined as \(i^2 = -1\).