- #51

SammyS

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Don't look at the discriminant for k2

3+k

1/2

(3+k)^2-4(2)(1/2)

=(3+k)(3+k)-4

=9+3k+3k+k^2-4

=k^2+6k+5

~~b^2 - 4ac~~

(6k)^2-4(k^2)(5)

(6k)(6k)-20k^2

36k^2-20k^2

16k^2

^{2}+ 6k + 5 = 0 .

Look again at what

k...

You want values of k for which the discriminant is non-negative. You have identified values of k for which the discriminant is zero.

Edit: To be clear, you are on the right track and doing well now.

Edit: And reading back to the original problem statement we want values of k for which the discriminant is negative.

^{2}+ 6k + 5

**is**the discriminant for the original quadratic equation.

Solve the inequality: k

^{2}+ 6k + 5 < 0 .

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