Answer:
- make sure calculator is in "radians" mode
- use the cos⁻¹ function to find cos⁻¹(.23) ≈ 1.338718644
Step-by-step explanation:
A screenshot of a calculator shows the cos⁻¹ function (also called arccosine). It is often a "2nd" function on the cosine key. To get the answer in radians, the calculator must be in radians mode. Different calculators have different methods of setting that mode. For some, it is the default, as in the calculator accessed from a Google search box (2nd attachment).
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The third attachment shows a graph of the cosine function (red) and the value 0.23 (dashed red horizontal line). Everywhere that line intersects the cosine function is a value of A such that cos A = 0.23. There are an infinite number of them. You need to know about the symmetry and periodicity of the cosine function to find them all, given that one of them is A ≈ 1.339.
The solution in the 4th quadrant is at 2π-1.339, and additional solutions are at these values plus 2kπ, for any integer k.
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Also in the third attachment is a graph of the inverse of the cosine function (purple). The dashed purple vertical line is at x=0.23, so its intersection point with the inverse function is at 1.339, the angle at which cos(x)=0.23. The dashed orange graph shows the inverse of the cosine function, but to make it be single-valued (thus, a <em>function</em>), the arccosine function is restricted to the range 0 ≤ y ≤ π (purple).
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So, the easiest way to answer the problem is to use the inverse cosine function (cos⁻¹) of your scientific or graphing calculator. (<em>Always make sure</em> the angle mode, degrees or radians, is appropriate to the solution you want.) Be aware that the cosine function is periodic, so there is not just one answer unless the range is restricted.
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I keep myself "unconfused" by reading <em>cos⁻¹</em> as <em>the angle whose cosine is</em>. As with any inverse functions, the relationship with the original function is ...
cos⁻¹(cos A) = A
cos(cos⁻¹ a) = a
AB- 3in.
BC- 5in.
CD- 7.2in.
sorry i don't really have an explanation I just looked at the picture and i guess imagined it in my head? lol sorry but here are the answers I hope that helps at least a little bit :))
The answer is B. because if you make an equation in the form y=mx+b then you can solve the equation by inputting x where x goes in the equation and solving. BTW the equation would be y=2x-1
Answer:
Step-by-step explanation:
Eek! Let's give this a go. Things we know:
acceleration of Bond in free fall is -9.8 m/s/s
velocity of the truck is 25 m/s
displacement Bond will travel when he jumps is -10 m
What we are looking for is the time it will take him to hit the top of the truck, knowing that the truck can travel from one pole to the next in 1 second.
Our displacement equation is
Δx = v₀t + 1/2at²
Filling in we have

Simplifying we get

This is a quadratic that needs to be solved however you personally solve quadratics. When you do that, you find that the times it will take Bond to drop that displacement is either -.37 seconds or 5.47 seconds. Many things in physics can be negative, like velocity and acceleration, but time NEVER will be. So it takes Bond 5.5 seconds to drop to the roof of the moving truck. That means that he needs to jump when the truck is between the 5th and the 6th poles away from him.
Good luck with this!
Cheers!