Answer:
see explanation
Step-by-step explanation:
Using the double angle identity for sine
sin2x = 2sinxcosx
Consider left side
cos20°cos40°cos80°
=
(2sin20°cos20°)cos40°cos80°
=
(2sin40°cos40°)cos80°
=
(sin80°cos80° )
=
(2sin80°cos80° )
=
. sin160°
=
. sin(180 - 20)°
=
. sin20°
=
= right side , thus proven
Answer:
F=0.4t
Step-by-step explanation:
Find the slope using the formula rise over run or y2-y2 over x2-x1
y2=72 y1=64 x2=25 x1=5
72-64/25-5=8/20=0.4
Given the function:

Let's find the amplitude and period of the function.
Apply the general cosine function:

Where A is the amplitude.
Comparing both functions, we have:
A = 1
b = 4
Hence, we have:
Amplitude, A = 1
To find the period, we have:

Therefore, the period is = π/2
The graph of the function is shown below:
The parent function of the given function is:

Let's describe the transformation..
Apply the transformation rules for function.
We have:
The transformation that occured from f(x) = cosx to g(x) = cos4x using the rules of transformation can be said to be a horizontal compression.
ANSWER:
Amplitude = 1
Period = π/2
Transformation = horizontal compression.