Question

class 11 test. help needed dear braily friends

Answer 1

Question -

The domain of definition of the function f(x) = √(9x-x^2) is

Solution -

We need to find the domain of the function f(x) = √(9x-x²)

Let us calculate it.

First of all , the value inside a square root can not be negative unless you have to solve in complex.

So

9x - x² ≥ 0

: x² ≤ 9x

For x ≠ 0

: x ≤ 9

If x is 0 , it is also valid. Now if x goes below 0 , has a negative value then the equation isn't satisfied.

Thus

• The least possible value of x is 0 .

• The maximum value of x is 9.

Or to conclude

The domain of the function is from 0 to 9, including both [ Including means square brackets and excluding means first bracket ]

> Domain is (D) [0, 9]

Hence the correct answer is D .

__________________________________________