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>
Here's y
y=<span><span><span><span>−<span>8x</span></span>+29
</span><span><span>−x</span>+<span>3
Hope this helps:)
</span></span></span></span>
Answer:
i think its c
Step-by-step explanation:
Question author, it's spelled pi not pie, and we use just use the Greek letter π. Students, demand better from your teachers.
1. Rectangular prism, aka a box. Volume is length times width times height.
V = 5×7×9 = 315 cubic feet
That's cubic feet of course, the product of three lengths. We didn't even need to do the problem, just look for the common answer and pick the one with the right units. I just saw that same pattern in a volume problem yesterday.
Answer: 315 cubic feet, first choice
2. Cylinder, volume is base area times height, πr²h. We have a radius of r=14/2=7 yd and h=8 yd. We're using π=3.14.
V = πr²h = 3.14(7²)(8) = 1230.88 cubic yds
Answer: 1230.9 cubic yards, last choice
Answer:
P = 
Step-by-step explanation:
Q = 3P + 2 ( subtract 2 from both sides )
Q - 2 = 3P ( isolate P by dividing both sides by 3 )
= P
