Question

Which expressions can be used to find mzBAC?

Select three options.
COS
6.9
12
O cos 5-1 (98)
12
O sin ¹52)
O sin ¹99
9.8
12
9.8
O tan-¹8
6.9

Answer 1

options 1 , 4 and 5

Explanation:

using the following trigonometric ratios in right triangle ABC

(1)

cos BAC =
`(adjacent)/(hypotenuse)` =
`(AC)/(AB)` =
`(6.9)/(12)` , then

∠ BAC =
`cos^(-1)` (
`(6.9)/(12)` ) ← option 1

(2)

sin BAC =
`(opposite)/(hypotenuse)` =
`(BC)/(AB)` =
`(9.8)/(12)` , then

∠ BAC =
`sin^(-1)` (
`(9.8)/(12)` ) ← option 4

(3)

tan BAC =
`(opposite)/(adjacent)` =
`(BC)/(AC)` =
`(9.8)/(6.9)` , then

∠ BAC =
`tan^(-1)` (
`(9.8)/(6.9)` ) ← option 5