English

Check if the following function has an inverse function. If yes, find the inverse function. f(x) = {x+7x<08-xx≥0 - Mathematics and Statistics

Advertisements
Advertisements

Question

Check if the following function has an inverse function. If yes, find the inverse function.

f(x) = `{(x + 7, x < 0),(8 - x, x ≥ 0):}`

Sum

Solution 1

f(x) = `{(x + 7, x < 0),(8 - x, x ≥ 0):}`

If x < 0, x + 7 < 7

If x ≥ 0, – x ≤ 0 so that 8 – x ≤ 8

∴ Range = `(- ∞, 8)`

∴ for y = 10, we cannot find x such that f(x) = y

∴ f is not onto

∴ f–1 does not exist.

shaalaa.com

Solution 2

f(x) = `{(x + 7, x < 0),(8 - x, x ≥ 0):}`

∴ f(– 1) = – 1 + 7 = 6

∴ f(2) = 8 – 2 = 6

∴ f(– 1) = f(2) but – 1 ≠ 2

∴ f is not one-one

∴ f–1 does not exist.

shaalaa.com
Algebra of Functions
  Is there an error in this question or solution?
Chapter 6: Functions - Exercise 6.2 [Page 128]

RELATED QUESTIONS

If f(x) = 2x2 + 3, g(x) = 5x − 2, then find f ° f


If f(x) = 2x2 + 3, g (x) = 5x − 2, then find g ° g


Check if the following function has an inverse function. If yes, find the inverse function.

f(x) = 5x2


Check if the following function has an inverse function. If yes, find the inverse function.

f(x) = 8


If f(x) = `{(x^2 + 3, x ≤ 2),(5x + 7, x > 2):}`, then find f(3)


If f(x) = `{(4x - 2",", x ≤ -3),(5",", -3 < x < 3),(x^2",", x ≥ 3):}`, then find f(– 3)


If f(x) = 2|x| + 3x, then find f(2)


If f(x) = 4[x] − 3, where [x] is greatest integer function of x, then find f(7.2)


If f(x) = 4[x] − 3, where [x] is greatest integer function of x, then find `"f"(- 5/2)`


If f(x) = 2{x} + 5x, where {x} is fractional part function of x, then find f(– 1)


If f(x) = 2{x} + 5x, where {x} is fractional part function of x, then find f(– 6)


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

|x + 4| ≥ 5


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

2|x| = 5


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

[x + [x + [x]]] = 9


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

{x} > 4


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

{x} = 0.5


Solve the following for x, where |x| is modulus function, [x] is greatest integer function, [x] is a fractional part function.

2{x} = x + [x]


Answer the following:

Find f ° g and g ° f: f(x) = 256x4, g(x) = `sqrt(x)`


Answer the following:

Solve the following for x, where |x| is modulus function, [x] is greatest interger function, {x} is a fractional part function

|x2 − x − 6| = x + 2


Answer the following:

Solve the following for x, where |x| is modulus function, [x] is greatest interger function, {x} is a fractional part function

−2 < [x] ≤ 7


Answer the following:

Solve the following for x, where |x| is modulus function, [x] is greatest interger function, {x} is a fractional part function

2[2x − 5] − 1 = 7


Answer the following:

Find (f ° g) (x) and (g ° f) (x)

f(x) = ex, g(x) = log x


Answer the following:

Find f(x) if g(x) = `1 + sqrt(x)` and f[g(x)] = `3 + 2sqrt(x) + x`


Answer the following:

Find (f ° f) (x) if f(x) = `x/sqrt(1 + x^2)`


Answer the following:

Find (f ° f) (x) if f(x) = `(2x + 1)/(3x - 2)`


For f(x) = [x] , where [x] is the greatest integer function, which of the following is true, for every x ∈ R.


If `a + pi/2 < 2tan^-1x + 3cot^-1x < b`, then a and b are respectively.


`int_0^4 x[x]  dx`, where [.] denotes the greatest integer function, equals ______


`int_0^3 [x]dx` = ______, where [x] is greatest integer function.


lf f : [1, ∞) `rightarrow` [2, ∞) is given by f(x) = `x + 1/x`, then f–1(x) is equal to ______.


If z ≠ 0, then `int_(x = 0)^100` [arg | z |] dx is ______.

(where [.] denotes the greatest integer function)


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×