यदि `sec alpha+tan alpha=2)` है तो `sin alpha` का मान क्या होगा ?( `0 lt a lt 90^(@))` है

Options

A. 0.4
B. 0.5
C. 0.6
D. 0.8

Answer

c

Explanation

`sec alpha+tan alpha=2` .....(i)
`sec alpha-tanalpha=(1)/(2)` .......(ii)
`sec alpha-tanalpha=(1)/(2) ` ........(ii)
Add equation (i) and (ii)
`sec alpha=2+(1)/(2)`
`sec alpha=(5rarrH)/(4rarrB)`

`sin alpha=(3)/(5)=0.6`