# What is the vertex form of #y=41x^2-3x+17#?

##### 1 Answer

The wording 'vertex form' is new to me but I am assuming it is completion of the square:

#### Explanation:

If I am wrong about the term then perhaps I am showing you something else that may prove useful.

Write as

At the moment I can use the equals because I have not changed any of the total values on the right hand side (RHS). However, the next stage does change the value on the right so at that point I must not use the equals sign.

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Consider the

We get

Suppose I rewrite (1) and use the

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Now square the bracket

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Add the constant ( the right still does not

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The way we have written the bracket introduces an error. Let me multiply the bracket out and you will see what I mean.

We have introduced the extra value of

To compensate for this we remove it by subtracting the same value

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So the vertex form (completing the square) is:

Adjust equation (3) by subtracting