Answer:
cos 4u = co^s2 2u - sin^2 2u
Step-by-step explanation:
cos 4u = co^s2 2u - sin^2 2u
Let 4u = 2x
cos 2x = cos^2 x - sin^ 2 x
cos (x+x) = cos^2 x - sin^ 2 x
Using cos(x+y) = cos(x)cos(y) -sin(x)sin(y)
cos(x) cos(x)- sin(x) sin (x)= cos^2 x - sin^ 2 x
cos^2 (x) -sin^2 (x) =cos^2 x - sin^ 2 x
Since this is true
cos 2x = cos^2 x - sin^ 2 x
This is true
Substituting 4u back for 2x
cos 4u = co^s2 2u - sin^2 2u
This is true
Answer:
you answer will be a binary number
Price of 3 shirts=$18*3=$54
Price of 2 pair of socks=2*$3.99=$7.98
Price of a pair of slack=$45
Total amount- $54+$7.98+ $45-$106.98
Sales tax rate = 8.5%
8.5% of total amount-8.5% of $106.98=
(8.5/100)*106.98-9.0933
Total amount Rick paid=$106.98+9.0933=$116.0733
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