cos4x = cos2x
We know that:
cos2x = 1-2cos^2 x
==> cos4x = 1-2cos^2 (2x)
Now substitute:
==> 1-2cos^2 (2x) = cos2x
==> 2cos^2 (2x) + cos2x - 1 = 0
Now factor:
==> (2cos2x -1)(cos2x + 1) = 0
==> 2cos2x -1 = 0 ==> cos2x =1/2 ==> 2x= pi/3
==> x1= pi/6 , 7pi/6
==> x1= pi/6 + 2npi
==> x2= 7pi/6 + 2npi
==> cos2x = -1 ==> 2x= pi ==> x3 = pi/2 + 2npi.
<span>==> x= { pi/6+2npi, 7pi/6+2npi, pi/2+2npi}</span>
You are only showing one pair of triangles
$ 33.82
Step-by-step explanation:
If Lou already had 6.1 gallons in the 15-gallon tank, then the amount of volume left to fill was;
15 – 6.1 = 8.9
Lou, therefore, spent the following amount to fill the gas tank;
8.9 * $3.80 = $ 33.82
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4,756 rounded to the nearest thousand is 5,000.
448 square inches.
The surface area of the box is 448 square inches so that is the least amount of paper needed to cover the box.