How to find the point of intersection for all values of m,c and a?
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Can someone please explain to me how to do question 22? Thanks!
Can someone please explain to me how to do question 22? Thanks!
1 Answer
The answer is (D). Set the two curves equal and solve for
Explanation:
To find the points of intersection of the straight line
We see from this that the curves do not intersect when the discriminant
Rearrange this condition:
If
If
So the answer is (D). Your written working on the photo shows that you're very nearly there already; you just need to note that when
NB There are two parameter regions that work, but only one is listed as an option in the question - they aren't looking for the complete solution of all possible regions, rather for you to say which of their options is part of the complete solution.