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Schachpapa
1 year ago

is something different than

The former can also be written as (x+3)(x-3) (3rd binary formula)

The second is (x+3)2

Edit:

I don’t know what you were thinking. The function looks like this:

An extreme point at H(3|216). N(5|0) and S(-3|0) are the two zero points, the latter also being the saddle point (and thus the turning point). Further turning point at W(1|128)

Edit2:

Now I’ll see what you did.

You took the first derivation:

f'(x) = -2 x3 – 6 x2 + 18 x + 54 and 0 set.

and divided by -2:

x3 + 3 x2 – 9 x -27 = 0

This is (x+3)(x+3)(x-3) a double zero point at -3 and a simple one at +3

If you recreate the task twice, i.e. once by (x+3) and once by (x-3), you will receive the first time (x2-9) = (x+3)(x-3) and the second time (x2 + 6x + 9) = (x+3)2

In both cases f’ has a double zero at -3 and a simple at +3. You get no other result, but only in a different order.

derBrathahn
1 year ago
Reply to  Schachpapa

You mean (x+3)(x-3)?

Schachpapa
1 year ago
Reply to  derBrathahn

Sure. Correct, thank you.

f0felix
1 year ago

In the second task, one does not see whether a minus or + is before 6x, so one cannot say the correct solution but if it is -6x, then the solution x1/2=3 and it is a double zero; at +6x is the solution x1/2=-3 and it is again a double zero;

you do not have an error in your 2nd invoice wthe discharge is correct;

But since you have calculated the same task, the derivation must be wrong;

f'(x)=-2x^3-6x^2-18x+54

you have completely different derivatives that do not fit the task

Florabest
1 year ago

I don’t understand your problem. You come to different results because it appears to be different functions.

In both invoices you could have dispensed with the pq formula, because you can see the solutions when looking at the functions. It’s simple binomes. Their solutions are obtained from the set of the zero product.

And at the second, it’s just a solution. Because a+0 and a-0 IMMER a results. This is because 0 is zero – the mathematician calls the 0 the neutral element of the addition.

Florabest
1 year ago

set of zero product.

In the first (x-3)*(x+3)=0 then you can see it.

In the second (x+3)*(x+3)=0, this is also trivial.

Schachpapa
1 year ago
Reply to  Florabest

In both invoices you could have dispensed with the pq formula

If you have a beautiful hammer (here PQ formula), everything looks like a nail. PQ formula always works. “Seeing solutions” requires thought and experience.

Florabest
1 year ago
Reply to  Schachpapa

The set of zero product is also a beautiful and precise tool…. and much easier to understand and notice than the pq formula.

derBrathahn
1 year ago

You have another function below? It’s clear that something else comes out or I don’t understand your problem?

at the top you have a zero at *3 and a zero at -3

at the lower one double zero point at -3 (that is, the graph only touches the x axis but does not pass)

Florabest
1 year ago

Could you pack this text in sentences that you can understand?

derBrathahn
1 year ago

Could you please do the whole job in the question?