Simplify x^2-9/x^2-3x
1 answer:
You might be interested in
Answer:
The correct options are:
Option B) is never zero.
Option F) When x=0, y≠0
Step-by-step explanation:
Consider the provided function.
When we substitute x=0 in above function we get:
When we substitute x=-1 in above function we get:
When we substitute x=1 in above function we get:
The above function is exponential function which does not pass through the origin and the range of the function is a positive number.
The graph of the function is shown in figure 1.
Now consider the provided options.
Option A) is always greater than or equal to 1.
The option is incorrect as the value of the function is less than 1 for negative value of x.
Option B) is never zero
The option is correct.
Option C) When y=0, x=0
The option is incorrect.
Option D) When x=0, y=4
When x=0 the value of y is 1.
Thus, the option is incorrect.
Option E) is zero when x=0
When x=0 the value of is 1.
Thus, the option is incorrect.
Option F) When x=0, y≠0
The option is correct as 0≠1.
Given:
A train travels 288 km at a uniform speed.
If the speed has been 4 km per hour more it would have taken one hour less for the same journey.
To find:
The initial speed of the train.
Solution:
Let x km/h be the initial speed on the train.
New speed of train = (x+4) km/h
We know that,
Time taken by the train initially to cover 288 km is hours.
New time taken by the train to cover 288 km is hours.
It is given that If the speed has been 4 km per hour more it would have taken one hour less for the same journey.
Splitting the middle term, we get
We know that the speed cannot be negative. So, the only possible value of x is 32.
Therefore, the speed of the train is 32 km/h.