@SALogics Yes, but when I see a number like 14 my first thought is not that it can be split up like that. Similarly when I see the number 399 my first thought wouldn't be 7^3+7^2+7. Is there some method to do that easily or is it just trial and error?
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x = ln2/ln3
Yes, you are right! ❤
It's non-obvious how you came up with the idea to split -14 into -8, -4 and -2. How would you solve it if it was -15 or -13?
Because 8 = 2³ and 4 = 2²
@SALogics Yes, but when I see a number like 14 my first thought is not that it can be split up like that. Similarly when I see the number 399 my first thought wouldn't be 7^3+7^2+7. Is there some method to do that easily or is it just trial and error?
@@adamnyback When we see m³ + m² + m then we think of spliting 14 = 2³ + 2² + 2
@@SALogics How would you solve it if it was 15 or 399 instead of 14?
@@adamnyback 399 = 7³ + 7² + 7 and 15 = 3³ - 3² - 3
T =3^x. T^3 + T^2 + T -14 =0. F(2) =0. F(T): (T-2). ĐỂ ĐƯA VỀ A.B =0
最初にxは実数とは書いていない。だから虚数解もある。
はい、あなたは正しいです！