Math Is Fun Forum

jacks

Member

Registered: 2012-11-21

Posts: 132

quadratic equation

If

are the roots of the equation

Then value of

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

I do not see any trick that is faster than computing the roots and slogging through the algebra.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: quadratic equation

hi jacks,

What I tried is 'messy' but does work.

Use fraction adding to combine the two fractions.  You'll get a complicated expression containing terms in alpha and beta.

Simplify with

Lots of simplification but not down to a very simple expression I'm afraid.

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

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Hi bob bundy,

Last edited by thickhead (2016-07-10 19:50:28)

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{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: quadratic equation

Thanks.  I stand corrected.  I'll re-try my simplification.  Let's hope it comes out nicely with this correction

Note: This change will affect alpha squared + beta squared as well.

LATER EDIT:

I should have said:

Working as before with these equations I got this:

There's a page of algebraic simplification involved and I often slip up with things like that so this may not be right.  I'll have a break and then try to check it.

Bob

Last edited by Bob (2016-07-10 20:38:33)

---

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

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Last edited by thickhead (2016-07-11 17:18:35)

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

jacks

Member

Registered: 2012-11-21

Posts: 132

Re: quadratic equation

Thanks bobbym, bob bundy, Thickhead

but answer given as 1

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

Hi;

The answer to what you posted is definitely not 1. But it is possible that you meant to post this

Notice the sign on c is negative not positive. This does have an answer of 1.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

jacks

Member

Registered: 2012-11-21

Posts: 132

Re: quadratic equation

Yes bobbym you are right, answer should be not equal to 1

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

Was the problem meant to be

?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

The equation should be

to get the answer 1.

Last edited by thickhead (2016-07-12 14:51:29)

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

Hi;

I think any p , not just p = 2 will give an answer of 1 in

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

I got it from each part of the expression setting equal to 1/2. last night it was too late  and I made an error in setting the middle term.

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{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

p = 24 also yields 1 as would many other p's.

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Last edited by thickhead (2016-07-14 19:24:33)

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Last edited by thickhead (2016-07-13 16:28:55)

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Now I understand my mistake in reverse book building. The 2 parts E_1 and E_2 have to be symmetrical but not necessarily equal.But analysis in #16 does not seem to have a hole.

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: quadratic equation

Hi;

But analysis in #16 does not seem to have a hole.

Do you still think one of the roots must be 0?

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

Hi;

But analysis in #16 does not seem to have a hole.

Do you still think one of the roots must be 0?

No, one of the roots equal to zero comes after the misconception that each part of the desired product must be 1/2. That part I have already clarified.
correction: I thought it was a product of #14 but it belongs to #16. I have to think.

Last edited by thickhead (2016-07-14 02:56:29)

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{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}

thickhead

Member

Registered: 2016-04-16

Posts: 1,086

Re: quadratic equation

---

{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}