Question

Find the value of trignomwtric function:
sec330°​

Answer 1

`(2√(3) )/(3)`

Explanation:

Using the identity

secx =
`(1)/(cosx)` and cos30° =
`(√(3) )/(2)` , then

sec330°

=
`(1)/(cos330)`

=
`(1)/(cos(360-330))`

=
`(1)/(cos30)`

=
`(1)/((√(3) )/(2) )`

=
`(2)/(√(3) )` ← rationalise the denominator

=
`(2)/(√(3) )` ×
`(√(3) )/(√(3) )`

=
`(2√(3) )/(3)`

Answer 2

Explanation:

sec330°

= 1 / cos330°

= 1 / cos30°

= 1 / (√3/2)

= 2/√3.