「22年 長崎大 医・工・歯・教育・薬・情報 3(1)」への2件のフィードバック

1. 1行でできませんでした。
   a + a ^−1 = 18
   https://www.wolframalpha.com/input?i=a+%2B+a+%5E%E2%88%921+%3D+18+&lang=ja

   a = 9 + 4 sqrt(5) , a ^(1 /1) + a^(−1/1), a ^(1 /2) + a^( − 1 /2 ),a^( 1 /3) + a^ (− 1/ 3)
   https://www.wolframalpha.com/input?i=a+%3D+9+%2B+4+sqrt%285%29+%2C+a+%5E%281+%2F1%29+%2B+a%5E%28%E2%88%921%2F1%29%2C++a+%5E%281+%2F2%29+%2B+a%5E%28+%E2%88%92+1+%2F2+%29%2Ca%5E%28+1+%2F3%29+%2B+a%5E+%28%E2%88%92+1%2F+3%29&lang=ja

   simply((2 (5 + 2 sqrt(5)))/sqrt(9 + 4 sqrt(5))), simply(1/(9 + 4 sqrt(5))^(1/3) + (9 + 4 sqrt(5))^(1/3) )
   https://www.wolframalpha.com/input?i=simply%28%282+%285+%2B+2+sqrt%285%29%29%29%2Fsqrt%289+%2B+4+sqrt%285%29%29%29%2C+simply%281%2F%289+%2B+4+sqrt%285%29%29%5E%281%2F3%29+%2B+%289+%2B+4+sqrt%285%29%29%5E%281%2F3%29++%29&lang=ja
   別の形
   {2 sqrt(5), 3}

   • aの解が2つありました。プロットより。
     厳密値a = 9 – 4 sqrt(5),a = 9 + 4 sqrt(5)
     近似値a≈0.055728,a≈17.944

     a = 9 -4 sqrt(5) , a ^(1 /1) + a^(−1/1), a ^(1 /2) + a^( − 1 /2 ),a^( 1 /3) + a^ (− 1/ 3)
     https://www.wolframalpha.com/input?i=a+%3D+9+-4+sqrt%285%29+%2C+a+%5E%281+%2F1%29+%2B+a%5E%28%E2%88%921%2F1%29%2C++a+%5E%281+%2F2%29+%2B+a%5E%28+%E2%88%92+1+%2F2+%29%2Ca%5E%28+1+%2F3%29+%2B+a%5E+%28%E2%88%92+1%2F+3%29&lang=ja
     (10 – 4 sqrt(5))/sqrt(9 – 4 sqrt(5)), 1/(9 – 4 sqrt(5))^(1/3) + (9 – 4 sqrt(5))^(1/3)
     別の形
     {2 sqrt(5), 3}

コメントは停止中です。