Question

(If cosA/2=1/2. find the value of sinA.)​

Answer 1

`\\ \rm\hookrightarrow cosA/2=1/2`

`\\ \rm\hookrightarrow 2cosA=2`

`\\ \rm\hookrightarrow cosA=1`

Now

`\\ \rm\hookrightarrow sinA=√(1-cos^2A)`

`\\ \rm\hookrightarrow sinA=√(1-1^2)`

`\\ \rm\hookrightarrow sinA=0`

Here

• A=0°