Answer:
see below
Step-by-step explanation:
The first part of the function, f(x) = -2x (for x < -1), is only graphed correctly in the first and third graphs.
The second part of the function, f(x) = -1 (for -1 ≤ x < 2) is only graphed correctly in the first graph, which also correctly graphs the third part of the function,
The appropriate choice is the first graph.
By definition, we have
So, we have to solve two different equations, depending of the possible range for the variable. We have to remember about these ranges when we decide to accept or discard the solutions:
Suppose that
In this case, the absolute value doesn't do anything: the equation is
We are supposing , so we can accept this solution.
Now, suppose that . Now the sign of the expression is flipped by the absolute value, and the equation becomes
Again, the solution is coherent with the assumption, so we can accept this value as well.
C
the sum to infinity of a geometric series =
where a is the first term and r the common ratio
= = 81 × 3 = 243
Answer:
s = 22.5 m
Step-by-step explanation:
the equation for the speed change of a coach moving along a straight section of the road and starting braking at a speed of 20 m / s has the form v (t) = 25-5t. Using integral calculus, determine the coach's braking distance.
v (t) = 25 - 5 t
at t = 0 , v = 20 m/s
Let the distance is s.
Let at t = t, the v = 20
So,
20 = 25 - 5 t
t = 1 s
So, s = 25 x 1 - 2.5 x 1 = 22.5 m