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Full Version: Graphical solving of systems of equations in the Function application.
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I still want to cover this topic in the Function app. This applies, of course, to finding graphical solutions to equations where the LN (x) and LOG (x) functions occur. I will give examples:
1. I solve graphically the system of equations: y = x ^ 2 -30 i y = LN (x)
We get 2 places of intersection. OKAY
2. Now he solves a graphically similar system of equations: y = x ^ 2 - 30 and y = LN (x - 2). Unfortunately, the calculator finds only one solution here, x = 5.59276. It does not show the second solution.
3. Now I change the function LN to LOG. Let's take a look at this.
y = x ^ 2 - 30 and y = LOG (x). We get 2 places of intersection. OKAY
4. Now we have: y = x ^ 2 -30 and y = LOG (x - 2). And here, unfortunately, as for LN, the calculator finds only one solution, x = 5.52697. It does not show the second solution.
Please correct this. And one more important note. All the above-mentioned systems of equations are solved well by the Advanced Graphing application.
The problem in these examples is that the root that the Graphing app doesn’t find is very close to 2: in your first example, the root is 2 + 5.109 x 10^(-12). In Home mode numbers on the Prime only have 12 digits, so this root cannot be found directly.
(I found the result above by replacing X by X+2 in each equation and solving for the new X.)

Nigel (UK)
(10-15-2022 10:41 AM)Nigel (UK) Wrote: [ -> ]The problem in these examples is that the root that the Graphing app doesn’t find is very close to 2: in your first example, the root is 2 + 5.109 x 10^(-12). In Home mode numbers on the Prime only have 12 digits, so this root cannot be found directly.
(I found the result above by replacing X by X+2 in each equation and solving for the new X.)

Nigel (UK)

Nice explanation thanks
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