Q) Use the discriminant 'b^2=-4ac' to solve the following:
i) Find the values of ' k ' for which the following equations have two separate roots.
Answer is 0>k>8
I solved the above to get
Now my question is that we know that k>8 but how do we figure k<0?
Is it because we are 100% that if k>8 from my final step then the other value must be smaller? (k<0)
ii) Find the values of ' k ' for which the following equations have no roots.
I solved this and got:
Answer is k=0
How is the answer k=0? I mean shouldn't 0<0 mean no solution or something?
iii) Sketch, on the same diagram, the graphs of and . Find the solution set of the inequality
Please tell me step by step on how to solve this question.
Thanks in advance!