Answer:
We have been given two function:
\(cos(\frac{n{\pi}}{2})\text{and} sin(\frac{n{\pi}}{2})\)
We need to tell their values so,
\(cos(\frac{n{\pi}}{2})= \left \{ {{-1^{\frac{n}{2}}};\text{n is even} \atop {0};\text{n is odd}} \right.\)
Put n=2 in the given above function cos(\frac{n{\pi}}{2}) we get: -1
Put n=3 in the function cos(\frac{n{\pi}}{2}) we get: 0
\(sin(\frac{n{\pi}}{2})=\left \{ {{-1^{\frac{n+3}{2}}};\text{n is odd} \atop {0};\text{n is even}} \right.\)
Put n=2 in the given above function cos(\frac{n{\pi}}{2}) we get: 0
Put n=3 in the function cos(\frac{n{\pi}}{2}) we get: -1
