Question

Solve for X in the given interval. sec x = -2sr3/3, for pi/2 less than or equal to x less than or equal to pi

Answer 1

B

Explanation:

Using the trig. identity

cos x =
`(1)/(secx)`

Given

secx = -
`(2√(3) )/(3)` , then

cos x = -
`(3)/(2√(3) )` ×
`(√(3) )/(√(3) )` = -
`(3√(3) )/(6)` = -
`(√(3) )/(2)` , thus

x =
`cos^(-1)` (-
`(√(3) )/(2)` ) =
`(5\pi )/(6)` → B