The average between 12.00 and 15.00 seconds
can be defined in a few different ways.
Way #1: (speed)
Average speed =
(1/2) (the speed at 12 seconds + the speed at 15 seconds) .
Way #2: (speed)
Average speed =
(1/3) (the distance covered between 12.00 and 15.00 seconds)
Way #3: (velocity)
Average velocity =
(1/3) (distance between location at 12 sec and location at 15 sec)
in the direction from location at 12 sec to location at 15 sec.
That's the best we can do with the combination of given and
not given information in the question.
Step-by-step explanation:
2⁶X5⁴X3¹²/2²x5²x3⁴
2⁴ × 5²×3⁸
7.
The point-slope form of the equation of a line is
y - y1 = m(x - x1)
where m is the slope, and (x1, y1) is a point on the line.
We are given two points, so we can find the slope.
slope = m = (y2 - y1)/(x2 - x1)
The slope of this line is
m = (-3 - 7)/(5 - (-15)) = -10/20 = -1/2
Since every choice has a 7 and a 15, we now use point (-15, 7) and slope -1/2.
y - y1 = m(x - x1)
y - 7 = -1/2(x - (-15))
y - 7 = -1/2(x + 15)
The base case of 
is trivially true, since
but I think the case of 
may be a bit more convincing in this role. We have by the inclusion/exclusion principle
with equality if 
.
Now assume the case of 
is true, that
We want to use this to prove the claim for 
, that
The I/EP tells us
and by the same argument as in the case, this leads to
By the induction hypothesis, we have an upper bound for the probability of the union of the 
through 
. The result follows.
