Question

HELPP! Problem is shown in photo. Please explain the process on how you found the answer

Answer 1

yup

Explanation:

u have the correct answer selected already on the picture u have on there

Answer 2

Answer: -33/65

Find cos(α + β) ?

Given:

• sinα = 4/5

• cosβ = 5/13

Find cosα given sinα is 4/5.

• opp/hyp = 4/5

Find adj =
`\sf √(hyp^2 - opp^2) = √(5^2 - 4^2) = 3`

• cosa = adj/hyp

• cosa = 3/5

Find sinβ given cosβ is 5/13

• adj/hyp = 5/13

Find opp =
`\sf √(hyp^2 - adj^2) = √(13^2 - 5^2) = 12`

• sinβ = opp/hyp

• sinβ = 12/13

Now use the formula cos(α + β) = cos(α)cos(β) - sin(α)sin(β)

So applying this:

• 3/5 × 5/13 - 4/5 × 12/13

• -33/65