The expression is:
cos (π / 5) cos (π/7) + sin (π/5) sin(π/7)
This expression can be reduced into a trigonometric function with one angle if we make use of the trigonometric identities. The appropriate identity is:
cos (A - B) = cos A cos B + sin A sin B
If we let
A = π / 5
B = π / 7
Therefore,
cos (π / 5) cos (π/7) + sin (π/5) sin(π/7) = cos (π/5 - π/7) = cos (2π/35)
Answer:
im pretty sure its 418. XD
Step-by-step explanation:
Know that:
sin(β)=Opposite/Hypotenuse
Therefore:
sin(54)=x/10
Therefore:
x=10*sin(54)
x=8.1 (To the nearest tenth)
Answer:
You have 1/60 of the original hair color left
Step-by-step explanation:
Add up the fractions
1/3 + 1/4 + 2/5
Get a common denominator of 60
1/3 * 20/20 + 1/4 * 15/15 + 2/5 * 12/12
20/60 + 15/60 + 24/60
59/60
The total is 1 or 60/60
60/60 - 59/60
1/60
You have 1/60 of the original hair color left
i think you multiply 4*80=320
