# Math Is Fun Forum

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## #1 2024-04-02 10:47:34

nycguitarguy
Member
Registered: 2024-02-24
Posts: 398

### Step Function aka Greatest Integer Function

Given f(x) = int(x/2), find a to c.

a. f(1.2)

b. f(1.6)

c. f(-1.8)

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## #2 2024-04-03 09:04:11

Bob
Registered: 2010-06-20
Posts: 10,109

### Re: Step Function aka Greatest Integer Function

Start with x 1.2, half it, take the integer part of the result.

When x is negative you'll need to check whether to round up or down to get the integer part.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #3 2024-04-04 05:45:53

nycguitarguy
Member
Registered: 2024-02-24
Posts: 398

### Re: Step Function aka Greatest Integer Function

Bob wrote:

Start with x 1.2, half it, take the integer part of the result.

When x is negative you'll need to check whether to round up or down to get the integer part.

Bob

I am sure what you mean here. Can you show me how this is done?

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## #4 2024-04-05 05:13:45

Bob
Registered: 2010-06-20
Posts: 10,109

### Re: Step Function aka Greatest Integer Function

The int function rounds all numbers down to the integer below the number.

Eg int(1.5) = 1

Int(1) = 1

Int(-1.5) = -2 not -1

For these questions, first you have to half the x input. Then apply the int function to the result.

Eg f(4.6) = int(2.3) = 2

f(-8.4) = int(-4.2) = -5

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #5 2024-04-05 06:20:51

nycguitarguy
Member
Registered: 2024-02-24
Posts: 398

### Re: Step Function aka Greatest Integer Function

Bob wrote:

The int function rounds all numbers down to the integer below the number.

Eg int(1.5) = 1

Int(1) = 1

Int(-1.5) = -2 not -1

For these questions, first you have to half the x input. Then apply the int function to the result.

Eg f(4.6) = int(2.3) = 2

f(-8.4) = int(-4.2) = -5

Bob

Let me see.

a. f(1.2)

f(x) = int(x/2)

f(1.2) = int(1.2/2)

f(1.2) int(0.6) = 0

b. f(1.6)

f(1.6) = int(1.6/2)

f(1.6) = int(0.8) = 0

c. f(-1.8)

f(-1.8) = int(-1.8/2)

f(-1.8) = int(0.9) = 0

You say?

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## #6 2024-04-05 08:29:20

Bob
Registered: 2010-06-20
Posts: 10,109

### Re: Step Function aka Greatest Integer Function

A and b good.

C error.  Half -1.8 is minus

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #7 2024-04-05 11:23:59

nycguitarguy
Member
Registered: 2024-02-24
Posts: 398

### Re: Step Function aka Greatest Integer Function

Bob wrote:

A and b good.

C error.  Half -1.8 is minus

Bob

c. f(-1.8)

f(-1.8) = int(-1.8/2)

f(-1.8) = int(-0.9) = -1

You say?

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## #8 2024-04-06 08:40:10

Bob
Registered: 2010-06-20
Posts: 10,109

### Re: Step Function aka Greatest Integer Function

Now correct.

B

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

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## #9 2024-04-06 11:30:51

nycguitarguy
Member
Registered: 2024-02-24
Posts: 398

Bob wrote:

Now correct.

B

Perfect.

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