Solution assignment 05 Addition and subtraction formulas

Return to Assignments Addition and subtraction formulas

Assignment 5

Show the following relation using some trigonometric formulas:

\sin(\displaystyle\frac{\pi}{2}-x)=\cos(x)

Solution

We can derive this formula from the unit circle, see also Trigonometry Unit circle and simple formulas. Now we use the following formula for the left-hand side:

\sin(\displaystyle\frac{\pi}{2}-x)=\sin(\displaystyle\frac{\pi}{2})\cos(x)-\sin(x)\cos(\displaystyle\frac{\pi}{2})=

=1.\cos(x)-\sin(x).0=\cos(x)

Return to Assignments Addition and subtraction formulas

0
Web Design BangladeshWeb Design BangladeshMymensingh