Use the 2 points to find the gradient of the line
Gradient = (y - y1)/(x - x1), y and y1 are the two different y values.
(2.3 - - 7.4)/(-4.3 - 1.3) = -97/56 = -1.732
Note: y and x both come from the same coordinate, and y1 and x1 also come from the same coordinates - (x , y), (x1 , y1)
Use the following to find the equation (x, x1, y, and y1 are not the same as the first part)
y - y1 = m(x - x1)
Where x2 and y2 is an intersection (one of the coordinates you used) and m is the gradient you found.
So...
y - 2.3 = -1.732(x - - 4.3)
You can simplify this if you are required to.
Using Descartes' Rule of Signs:
The signs are: - + - + - +
There are 5 signs changes in this sequence, so there could be either 5, 3, or 1 positive roots.
If we negate the terms with odd numbers (x^5, x^3), we end up with the signs: - - - - - +
Since there is 1 sign change, there can be only 1 negative root.
This means the positive and negative roots can either be 6, 4, or 2.
Since the total number of roots cannot exceed 6, there are either 0, 2, or 4 complex roots.
Answer:
3n/8 ≤ 13
Step-by-step explanation:
