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is there a good way to get this value by hand?
(without a Calculator) Log (base 2) of 3
https://www.youtube.com/watch?v=X6C5hGpWW5A
This clip shows how to derive
1.5 < Log2(3) < 1.6666666......
i wonder if there's a way to get better (and better) approximations.
HenHanna <HenHanna@dev.null> writes:
is there a good way to get this value by hand?
(without a Calculator) Log (base 2) of 3
https://www.youtube.com/watch?v=X6C5hGpWW5A
This clip shows how to derive
1.5 < Log2(3) < 1.6666666......
i wonder if there's a way to get better (and better) approximations.
Is it possibly you can summarize he gist of it in here so we can
discuss?
Did you take calculus in college and if so, did you ever learn the limit definition of the derivative?
On Mon, 18 Nov 2024 14:51:15 +0000, Daniel wrote:
HenHanna <HenHanna@dev.null> writes:
is there a good way to get this value by hand?
(without a Calculator) Log (base 2) of 3
https://www.youtube.com/watch?v=X6C5hGpWW5A
This clip shows how to derive
1.5 < Log2(3) < 1.6666666......
i wonder if there's a way to get better (and better) approximations.
Is it possibly you can summarize he gist of it in here so we can
discuss?
Did you take calculus in college and if so, did you ever learn the limit
definition of the derivative?
i thnk... i knew the Epsilon-Delta def. when i was 13.
Log2(3) = x
so 2^x =3 ---------- Square both sides
2^(2x) = 9 ------ We know that 2^3 = 8
2^(2x) > 2^3 ---- (2^power is monotonic) (monotonically increasing)
2x > 3
x > 1.5
We get x < 1.6666...... by Cubing both sides
i wonder if there's a way to get better (and better) approximations.
i wonder if there's a way to get better (and better) approximations.
In article <97e7e6fb078310c8d4d600c247847957@www.novabbs.com>,
HenHanna <HenHanna@dev.null> wrote:
i wonder if there's a way to get better (and better) approximations.
Look for more powers of 2 near to powers of 3.
For example,
3^7 (= 2187) > 2^11 (= 2048), so 3 > 2^(11/7), so log2(3) > 11/7 =
1.571+
3^10 (= 59049) < 2^16 (= 65536), so 3 < 2^(16/10), so log2(3) < 10/6 =
1.6
3^12 is very close to 2^19, so log2(3) is very close to 19/12 = 1.583+
-- Richard
Look for more powers of 2 near to powers of 3.
HenHanna <HenHanna@dev.null> writes:
On Mon, 18 Nov 2024 14:51:15 +0000, Daniel wrote:
HenHanna <HenHanna@dev.null> writes:
is there a good way to get this value by hand?Is it possibly you can summarize he gist of it in here so we can
(without a Calculator) Log (base 2) of 3
https://www.youtube.com/watch?v=X6C5hGpWW5A
This clip shows how to derive
1.5 < Log2(3) < 1.6666666......
i wonder if there's a way to get better (and better) approximations. >>>
discuss?
Did you take calculus in college and if so, did you ever learn the limit >>> definition of the derivative?
i thnk... i knew the Epsilon-Delta def. when i was 13.
Log2(3) = x
so 2^x =3 ---------- Square both sides
2^(2x) = 9 ------ We know that 2^3 = 8
2^(2x) > 2^3 ---- (2^power is monotonic) (monotonically increasing)
I've been out of college for twenty years and, even though I studied
math, there's more rust than anything. I see you chose the closest cube
from 9 to achieve a clean cube root. Which operation did you
do to get 2x > 3? Did you log both sides? Don't hit me if that's a
stupid question.
2x > 3
x > 1.5
We get x < 1.6666...... by Cubing both sides
How do achieve a result of 1.666666 by cubing 1.5? I get 1.5^3 = 3.375.
i wonder if there's a way to get better (and better) approximations.
Ever visit sci.math? I'm in there, perhaps we could crosspost this into
that NG and include them in the conversation. Oh, I will.
so 2^x =3 ---------- Square both sides
Good to see you in a.u.e., Richard!
HenHanna <HenHanna@dev.null> writes:
On Mon, 18 Nov 2024 14:51:15 +0000, Daniel wrote:
HenHanna <HenHanna@dev.null> writes:
is there a good way to get this value by hand?Is it possibly you can summarize he gist of it in here so we can
(without a Calculator) Log (base 2) of 3
https://www.youtube.com/watch?v=X6C5hGpWW5A
This clip shows how to derive
1.5 < Log2(3) < 1.6666666......
i wonder if there's a way to get better (and better) approximations. >>>
discuss?
Did you take calculus in college and if so, did you ever learn the limit >>> definition of the derivative?
i thnk... i knew the Epsilon-Delta def. when i was 13.
Log2(3) = x
so 2^x =3 ---------- Square both sides
2^(2x) = 9 ------ We know that 2^3 = 8
2^(2x) > 2^3 ---- (2^power is monotonic) (monotonically increasing)
I've been out of college for twenty years and, even though I studied
math, there's more rust than anything. I see you chose the closest cube
from 9 to achieve a clean cube root. Which operation did you
do to get 2x > 3? Did you log both sides? Don't hit me if that's a
stupid question.
2x > 3
x > 1.5
We get x < 1.6666...... by Cubing both sides
How do achieve a result of 1.666666 by cubing 1.5? I get 1.5^3 = 3.375.
i wonder if there's a way to get better (and better) approximations.
Ever visit sci.math? I'm in there, perhaps we could crosspost this into
that NG and include them in the conversation. Oh, I will.
In article <97e7e6fb078310c8d4d600c247847957@www.novabbs.com>,
HenHanna <HenHanna@dev.null> wrote:
i wonder if there's a way to get better (and better) approximations.
Look for more powers of 2 near to powers of 3.
For example,
3^7 (= 2187) > 2^11 (= 2048), so 3 > 2^(11/7), so log2(3) > 11/7 =
1.571+
3^10 (= 59049) < 2^16 (= 65536), so 3 < 2^(16/10), so log2(3) < 10/6 =
1.6
3^12 is very close to 2^19, so log2(3) is very close to 19/12 = 1.583+
-- Richard