Evaluating Functions (Intro to Function Notation)

Learn how to evaluate functions in this video tutorial by Mario's Math Tutoring. We discuss function notation and how to solve for the input and output of a function in four separate examples.

0:20 How to evaluate functions
0:34 Example 1 Evaluate f(2) for f(x)=2x^2 - 3x + 1
1:20 Example 2 Evaluate g(-3) for g(x)= -5x - 10
1:53 Example 3 Evaluate f(x+h) for f(x) = 4x^2 - x
3:23 Example 4 Find x when m(x) = 6 for m(x) = x^2 - 3

Related Videos:

Composition of Functions

More Difference Quotient Examples

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[noahmcfate]

Mario, you are a genuine blessing upon this world, i thank you for making these.

[platedbycee]

People that understand math I tell you are BLESSED because all of these numbers and letters are driving me crazy.

[syd]

Awesome video! My teacher spent an hour teaching us this and I didn't understand any of it. This 4 minute video helped me way more. Thanks!!

[aliciabuckner]

Me watching this while I’m taking my test 👁👄👁

[elijonking]

I was looking for this for hours and u explained it in one second

[plandy]

I missed 2 weeks of geometry one and was so confused. You are a lifesaver man

[nickmelville]

I was on a roll... Then you started doing #3 😵😵😵

[aundreataylor]

Thank you. This is a good refresher for my calc class :)

[scarlettsanders]

You lost me on the 3rd one!😂 But you definitely explained a lot better! Thanks so much!

[itsrobloxianjenn]

I’m so glad there are yt videos explaining all types of math units 😫

[beighcream]

THANK YOU SO MUCH! THIS IS A HUGE HELP!!!

[Paul-wwht]

Thanks for the step by step explanations.

[dnlic]

this guy teaches better than my real teacher lmao

[dasorthebeast]

dude you saved my math grades. thanks so much

[Cybrisk]

#3 Helped me crack the code. Thank you so much, holy smokes. The homework program would give me the correct answer without walking through the whole thing and it seemed like it was pulling numbers out of nowhere.

My answer: x^2 + 9x + 60
real answer: x^2 + 17x + 60

All because I didn't understand how the exponent works with distributive property apparently. You're a lifesaver.

[nurainalfierabtabdrazak]

The teacher is handsome.I study with passion

[MN-omyi]

thank you so much man 🙏 i didn’t get how to do this and i have a quiz in it but this video really helps

[pandabear]

But how do you solve it if its like
-5 × f(4)-1=1-3/4(4)
Or
1/3 × f(-8)=(-8)2-5(-8)+7
What do you do with the number that your not plugging in

[jonanderson]

you made me want to do math thx for a legend

[chickuna]

what do you do when there is a number before the "f" in "f(x)"? an example is:
-2f(x)