Question

Find sect 。A)B)op回?2121

Answer 1

We will operate as follows:

`x=\frac{\sqrt[]{21}}{5}`
`y=(2)/(5)`

Then:

`r^2=(\frac{\sqrt[]{21}}{5})^2+((2)/(5))^2\Rightarrow r=1`

Then we calculate cosine in order to determine the secant:

`\cos (\theta)=(x)/(r)\Rightarrow\cos (\theta)=\frac{\frac{\sqrt[]{21}}{5}}{1}\Rightarrow\cos (\theta)=\frac{\sqrt[]{21}}{5}`

Now, the secant:

`\sec (\theta)=(1)/(\cos(\theta))\Rightarrow\sec (\theta)=\frac{1}{\frac{\sqrt[]{21}}{5}}`
`\Rightarrow\sec (\theta)=\frac{5}{\sqrt[]{21}}=\frac{5\sqrt[]{21}}{21}`

So, the soluton would be option B.