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    Find the value k for which 5x^2-2x+k=0 has exactly one solution.

    What should i do to work this out
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    If it has one solution, that means the roots are equal hence b^2-4ac=0. Plug that in and solve.
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    Are u familiar with the roots of a quadratic.

    For a quadratic ax^2+bx+c

    If b^2-4ac>0 then the quadratic has two real roots.

    If b^2-4ac=0 then the quadratic has 1 real root.

    If b^2-4ac<0 then the quadratic has no real roots.
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    (Original post by thekidwhogames)
    If it has one solution, that means the roots are equal hence b^2-4ac=0. Plug that in and solve.
    Thanks that has worked.
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    (Original post by Shaanv)
    Are u familiar with the roots of a quadratic.

    For a quadratic ax^2+bx+c

    If b^2-4ac>0 then the quadratic has two real roots.

    If b^2-4ac=0 then the quadratic has 1 real root.

    If b^2-4ac<0 then the quadratic has no real roots.
    Thanks, am i right in saying k=1/5
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    (Original post by FinnManley)
    Thanks, am i right in saying k=1/5
    Yes.
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    (Original post by FinnManley)
    Thanks, am i right in saying k=1/5
    Yes thats correct. An alternative solution is to note that if a quadratic has just one solution then that means it can be written in the form a(x+b)^2 e.g it has no constant term when completing the square and this will easily give you the value of k.
 
 
 
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