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# Maths homework help please - asap watch

1. Find the value of k which results in the equation kx2 (sqaured) + 2kx -1 = 0having
equal roots, given that k is not equal to 0?
2. You must use the discriminant, making it equal 0 because the answer has equal roots.

Try that and then show me your working.
3. (Original post by h8skoooooool)
You must use the discriminant, making it equal 0 because the answer has equal roots.

Try that and then show me your working.
I am not sure what to do

b2-4ac=0

a=k b=2k c=-1

2k2-4(k)(-1)=0
4k2-4k=0
4k(k+1)=0 im not sure if thats right, quite confused what to do next
4. yes now solve for k
5. (Original post by Misshussain23)
I am not sure what to do

b2-4ac=0

a=k b=2k c=-1

2k2-4(k)(-1)=0
4k2-4k=0
4k(k+1)=0 im not sure if thats right, quite confused what to do next
That's correct!! Now find k like you would from any other quadratic equation.
Here's a clue, there's two answers and one of them is zero (though looking at the original question, just ignore the answer of 0)
6. (Original post by Misshussain23)
Find the value of k which results in the equation kx2 (sqaured) + 2kx -1 = 0having
equal roots, given that k is not equal to 0?
If it ever mentions roots (I'm assuming this is C1) in a C1 paper/question then use the discriminant of a quadratic equation (b^2-4ac)

Just be careful, remember b is equal to 2k not 2. Things like that can cost you marks.
7. (Original post by h8skoooooool)
That's correct!! Now find k like you would from any other quadratic equation.
Here's a clue, there's two answers and one of them is zero (though looking at the original question, just ignore the answer of 0)
okay thank you soo much for your help!
8. (Original post by AlphaArgonian)
If it ever mentions roots (I'm assuming this is C1) in a C1 paper/question then use the discriminant of a quadratic equation (b^2-4ac)

Just be careful, remember b is equal to 2k not 2. Things like that can cost you marks.
alright, thank you!
9. (Original post by Misshussain23)
alright, thank you!
My pleasure

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