<span>let y = sec^2 ( pi x )
y' = 2 sec ( pi x ) sec( pi x ) tan ( pi x ) pi
y' = 2pi sec^2 ( pi x ) tan ( pi x )
y''= 2pi sec^2 ( pi x ) * sec^2 ( pi x ) * pi + 2pi tan ( pi x ) * 2pi sec^2 ( pi x ) tan ( pi x )
y'' = 2 pi^2 sec^4 ( pi x ) + 4 pi^2 sec^2 ( pi x ) tan^2 ( pi x )</span>
The correct answer is -b+12
Answer:
The answer is b. But you asked for the thought process so...
Step-by-step explanation:
Let speed of the 1st trip x miles / hr. and speed of the 2nd trip 3x / hr.
We know that
Speed = Distance/Time.
Or, Time = Distance/Speed.
So, the time taken to cover a distance of 50 miles on his first trip = 50/x hr.
And the time taken to cover a distance of 300 miles on his later trip = 300/3x hr.
= 100/x hr.
So we can clearly see that his new time compared with the old time was: twice as much.
Have a great day :)
The given equations are:
5x - 2y = 88
3x + 4y = 58
Multiplying the 1st equation by 2, we get the new set of equations as:
10x - 4y = 176
3x + 4y = 58
Adding the two equations, we get:
10x - 4y + 3x + 4y = 176 + 58
13x =234
x = 18
Using the value of x in 1st equation, we get:
5(18) - 2y = 88
- 2y = 88 -5(18)
-2y = -2
y = 1
So, the solution of the equation is (18, 1)
