Can you please show how you worked it out or explain it a little bit.
Find the values of K for which the equation 2x^2+3kx+9=0 has: a) No solution b)one solution c)two solutions?
Since the discriminant of the quadratic formula determines the Nature of roots. we can use it to solve for the value of k
If b² - 4ac %26gt; 0 two solutions
If b² - 4ac = 0 one solution
If b² - 4ac %26lt; 0 no solution
a = 2 b = 3k c = 9
(3k)² - 4(2)(9) = 0
9k² - 72 = 0
9k² = 72
k² = 8
k = 2√2
when k = 2√2 it has only one solution
k %26lt; -2√2 or k %26gt; 2√2 ---------------- 2 solutions
-2√2 %26lt; k %26lt; 2√2 --------- no solutions
Reply:check determinant
9k^2-72=0 for 1 soln
k=+-sqrt8
9k^2-72%26gt;0 for 2 soln
k^2%26gt;8
k%26gt;sqrt8 or k%26lt;-sqrt8
for no soln, -sqrt8%26lt;k%26lt;sqrt8
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