Derive a formula for sin( in terms of and for all real numbers

sin (2α) = 2 sin (α) cos (α)

Step-by-step explanation:

We departure from the sin of a sum of angles  

sin ( α + β ) = sinα *cosβ + sinβ *cosα

if α = β   ⇒  sin (α + α ) = sin(α) *cos(α) + sin(α)*cos(α)

sin (2α) = 2 sin (α) cos (α)

the answer is a if my teacher taught me correct

hi there!

step-by-step explanation:

a roof pitch is basically for every inch rise there is 12 inches run.

the height of the roof is also known as the rafter.

formula: rafter^2 = rise^2 + run^2

rafter^2 = 5^2 + 12^2

rafter^2 = 25 + 144

rafter ^2 = 169"^2

the height of the roof from the lowest point to the highest point is 169"^2.

hope this : )