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What kind of equation is this? I don't get it


onemind

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Hi,

I have never really been a math type of person and am taking a intro to math course at uni.

I am asked to solve an equation in the same format as the one below and indicate clearly the method used.

The trouble is I have no idea how to do it :)

 

[math]

{6}/{y} + {8}/{y^2} = -1

[/math]

 

I would really appreciated any help.

Thanks :)

 

edit: I don't know how to make fractions with latex :)

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Hi again.

I thought I had it figured out but I am confused again :)

When I multiply it by y^2 I get

[math]

6y+8=-y^2

[/math]

then i set the right hand side to 0 to get

[math]

y^2+6y+8=0

[/math]

this is general quadratic form isn't it?

So I plug the coefficients into the quadratic formula and get

-2, -4

 

What are these numbers?

If I put them into the original quadratic form i get

-7,-3.5

I don't get it :)

Thanks again

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hi again

when i type [math]6/-2+8/-2^2[/math]

into my calculator it gives me -5

by hand i get 6/-2= -3 8/-2^2 = -2

so -3+(-2)= -5

 

What am I doing wrong?

 

 

when you type it into your calc you are probably getting an order of operations problem. put parentheses around the right stuff and it should work.

 

as for by hand:

 

6/-2= -3 but -2^2= 4, not negative 4. so 8/-2^2= 2 not -2

 

-3 + 2 = -1

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I exprienced this same problem when I was a little boy. Just remember that when you type -2^2 in your calculator, the calculator interprets it as [math]-(2^2)[/math] and not [math](-2)^2[/math].

 

[math]-(2^2) = -(4) = -4[/math]

 

[math](-2)^2 = -2 \times -2 = 4[/math] (remember that negative times negative equals a positive)

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