Solve example on various calculators
12-09-2023, 01:19 PM
Post: #2
 Albert Chan Senior Member Posts: 2,703 Joined: Jul 2018
RE: Solve example on various calculators
Cas> zeros((x+1) * sqrt(x*x-2*x-1))

[-1, √2+1, -√2+1]

By hand:

f = (x+1) * sqrt(x*x-2*x-1)
ln(f) = ln(x+1) + 1/2 * ln(x*x-2*x-1)
f'/f   = 1/(x+1) + (x-1)/(x*x-2*x-1) = 1/(x+1) + 1/((x-1) - 2/(x-1))

f'/f is rational polynomial, without sqrt.

f = 0      → f'/f = ±∞      → x = -1, 1±√2
 « Next Oldest | Next Newest »

 Messages In This Thread Solve example on various calculators - lrdheat - 12-09-2023, 02:38 AM RE: Solve example on various calculators - Albert Chan - 12-09-2023 01:19 PM RE: Solve example on various calculators - lrdheat - 12-09-2023, 03:04 PM RE: Solve example on various calculators - C.Ret - 12-09-2023, 06:19 PM RE: Solve example on various calculators - lrdheat - 12-09-2023, 07:24 PM RE: Solve example on various calculators - Marco Polo - 12-09-2023, 10:08 PM RE: Solve example on various calculators - C.Ret - 12-10-2023, 03:19 AM RE: Solve example on various calculators - Gene222 - 12-12-2023, 04:21 PM RE: Solve example on various calculators - lrdheat - 12-10-2023, 04:32 AM RE: Solve example on various calculators - carey - 12-10-2023, 09:27 AM RE: Solve example on various calculators - Albert Chan - 12-10-2023, 04:05 PM RE: Solve example on various calculators - lrdheat - 12-10-2023, 02:28 PM

User(s) browsing this thread: 1 Guest(s)