It's difficult to make out what the force and displacement vectors are supposed to be, so I'll generalize.
Let <em>θ</em> be the angle between the force vector <em>F</em> and the displacement vector <em>r</em>. The work <em>W</em> done by <em>F</em> in the direction of <em>r</em> is
<em>W</em> = <em>F</em> • <em>r</em> cos(<em>θ</em>)
The cosine of the angle between the vectors can be obtained from the dot product identity,
<em>a</em> • <em>b</em> = ||<em>a</em>|| ||<em>b</em>|| cos(<em>θ</em>) ==> cos(<em>θ</em>) = (<em>a</em> • <em>b</em>) / (||<em>a</em>|| ||<em>b</em>||)
so that
<em>W</em> = (<em>F</em> • <em>r</em>)² / (||<em>F</em>|| ||<em>r</em>||)
For instance, if <em>F</em> = 3<em>i</em> + <em>j</em> + <em>k</em> and <em>r</em> = 7<em>i</em> - 7<em>j</em> - <em>k</em> (which is my closest guess to the given vectors' components), then the work done by <em>F</em> along <em>r</em> is
<em>W</em> = ((3<em>i</em> + <em>j</em> + <em>k</em>) • (7<em>i</em> - 7<em>j</em> - <em>k</em>))² / (√(3² + 1² + 1²) √(7² + (-7)² + (-1)²))
==> <em>W</em> ≈ 5.12 J
(assuming <em>F</em> and <em>r</em> are measured in Newtons (N) and meters (m), respectively).
Answer:
-3.84
Step-by-step explanation:
Answer:
(d) 0.8736
Step-by-step explanation:
Unless you have a table of the normal distribution available, this is a calculator problem. Your calculator, or any spreadsheet, can tell you the probability is ...
P(-1.23 ≤ z ≤ 2.12) ≈ 0.8736
Answer:
You will break even on the car wash when you buy 13.5 gallons. As long as you buy that or more, it is cheaper to get the car wash.
Step-by-step explanation:
In order to find this, we need to create equations for both situations. If we let x equal the amount of gallons purchased, we can model the first equation as:
f(x) = 3.35x
And the second equation as:
f(x) = 3.05x + 4.05
Then to find when they equal each other, we can set the two equations equal to each other and solve for x.
3.35x = 3.05x + 4.05
0.30x = 4.05
x = 13.5
This means once you buy 13.5 gallons, the prices will be the same. Any amount over that and the car wash will be cheaper
Answer:
4z
Step-by-step explanation:
brainliest please