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_Mayday_
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[SOLVED] Discriminant Question
The Equation:
[itex]x^2 + kx + 8 = k[/itex]
has no real roots
(a) Show that [itex]k[/itex] satisfies [itex] k^2 + 4k - 32 (is.smaller.than) 0[/itex]
(b) Hence find the set of possible values of [itex]k[/itex]Attempt
(a) First I will put it in the form:
[itex]ax^2 + bx + c = 0[/itex]
[itex]x^2 + kx + 8 = k[/itex]
a = 1, b = k, c = 8
Now I will put this into the discriminant.
[itex]b^2 - 2ac (is.smaller.than) k[/itex]
[itex]k^2 - 16 (is.smaller.than) k[/itex]
Where do I go from here??
Thanks for any help!_Mayday_
The Equation:
[itex]x^2 + kx + 8 = k[/itex]
has no real roots
(a) Show that [itex]k[/itex] satisfies [itex] k^2 + 4k - 32 (is.smaller.than) 0[/itex]
(b) Hence find the set of possible values of [itex]k[/itex]Attempt
(a) First I will put it in the form:
[itex]ax^2 + bx + c = 0[/itex]
[itex]x^2 + kx + 8 = k[/itex]
a = 1, b = k, c = 8
Now I will put this into the discriminant.
[itex]b^2 - 2ac (is.smaller.than) k[/itex]
[itex]k^2 - 16 (is.smaller.than) k[/itex]
Where do I go from here??
Thanks for any help!_Mayday_