The answer is the second one, 6x2 - 4
The way to do this is to set up a 30 degree angle in a coordinate plane in the first quadrant. I say the first quadrant since the first quadrant goes from 0 to 90 degrees and 30 falls right in that interval. Using the positive x-axis as the initial ray of the 30 degree angle and the terminal ray of the angle as the hypotenuse of a right triangle, if we drop a height from the end of the terminal ray to the x-axis we have formed said right triangle. The angle at the origin is the 30 degree angle. According to the Pythagorean triple for a 30-60-90 triangle, the side across from the 30 degree angle measures 1, which is the height of our triangle. The side across from the 60 degree angle is square root of 3, which is the base of our triangle, and the hypotenuse is 2. The cos identity is the ratio that utilizes the side adjacent to the reference angle over the hypotenuse, which for us is
. That's the third choice down. Finding an "exact" value means that they want you to NOT express your answer in decimal form.
I need more info to help you on this
Answer:
Waves superimpose upon each other when they collide, while objects do not
Step-by-step explanation:
The main difference between the collision of waves and the collision of objects is simply the superposition principle.
When waves collide, they do not do so in the same way objects do. The superposition principle explains that waves can either collide in a constructive or destructive manner.
Case A: Waves colliding in a constructive manner
When waves collide in a constructive manner, this means that they are in phase, in simpler terms, it means that they have the same shape as they move through space-time. Constructive collision leads to a formation of a bigger wave with a higher amplitude. This is how stereo speakers operate. They produce louder sounds by releasing the same audio waves, causing them to superimpose upon each other.
Case B: Waves colliding in a destructive manner:
When waves are out of phase(i.e do not have the same shape as they move through space-time) and they collide, they try to cancel each other out, leading to a new wave with a weaker amplitude. This is how noise-cancelling headphones work. They emit an equal and opposite wave sound to the noise around your ears, thus cancelling it out.