Synthetic Substitution

Learn how to do synthetic substitution in this math video tutorial by Mario's Math Tutoring. We also discuss direct substitution and the remainder theorem. We go through 3 examples step by step.

0:11 What is Direct Substitution and How to Do It
0:49 Example 1 Find f(3) for f(x)=2x^2 - 3x + 7 Using Synthetic
1:54 Example 2 Find f(-1) for f(x)=4x^5 -3x^3 + 7x^2 + 1
3:10 Example 3 Find g(2) for g(x)=3x^4 -2x + 1

Related Videos:

How to do Synthetic Division

Remainder Theorem

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[Msalkk]

Thanks for the help, Mario! Really zoned out during online math class today so this video was all I needed to understand.

[ryanjohnson]

where did you get the 3 from in the first problem

[EnzeXiang]

Thanks for help, It is so helpful to me

[asian_sensation_]

whats the point of having all of those extra numbers if u could just multiply it by the last coefficient?

[ZiggyZiggurat]

I still don’t understand the second example

[notthedd]

how'd you teach this in 5 minutes and I got it but I didn't get it after a whole class in school

[hyunjinsdearbread]

Thank you sir. But are the last ones the only answer? Or the whole numbers below?

[ExposingEvil_]

So I ran into this problem:


8x^2-2x find f(1/2) -> Would I add a zero to the end to complete the descending order or would I add two zeros to complete the constant? I got 1 for an answer with only 1 zero, and 1 with direct subsitution. Would I add the extra 0 for the constant or no? (I think that would bring me to a negative, so maybe thats why it won't work?)


Anyways, excellent video! Where is #3 btw? The answer I got 45

[krkn]

how do you know to put a zero down I dont undersstand

[kimimasangcay]

How did you get 3 from the 1st onewtf?