Answer:
3.5 hours
Step-by-step explanation:
Speed of train X=30 mph
Speed of train Y=40 mph
Relative speed When the two trains travelling in same direction
Relative speed=40-30=10 mph
Total distance =25+10=35 miles
We have to find the time when train Y is 10 miles ahead of train X.
We know that
Time=
Using the formula
Then, we get
Time=
Hence, it will be 3.5 hours until train Y is 10 miles ahead of train X.
Answer:
The Taylor series of f(x) around the point a, can be written as:

Here we have:
f(x) = 4*cos(x)
a = 7*pi
then, let's calculate each part:
f(a) = 4*cos(7*pi) = -4
df/dx = -4*sin(x)
(df/dx)(a) = -4*sin(7*pi) = 0
(d^2f)/(dx^2) = -4*cos(x)
(d^2f)/(dx^2)(a) = -4*cos(7*pi) = 4
Here we already can see two things:
the odd derivatives will have a sin(x) function that is zero when evaluated in x = 7*pi, and we also can see that the sign will alternate between consecutive terms.
so we only will work with the even powers of the series:
f(x) = -4 + (1/2!)*4*(x - 7*pi)^2 - (1/4!)*4*(x - 7*pi)^4 + ....
So we can write it as:
f(x) = ∑fₙ
Such that the n-th term can written as:

Answer:
A link for a calculator that I use for ratios
Step-by-step explanation:
https://www.calculatorsoup.com/calculators/math/ratios.php
Answer:
x={-1,1,3,5}
Step-by-step explanation:
x={-1,1,3,5}
Step 1: remove parentheses
1-7+2.5
step 2:simplify 1-7 to -6
-6+2.5
step 3 :simplify
-3.5
the answer is -3.5