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数学 高校生

命題の証明 3の倍数でないことをいうため、3×整数+1 または3×整数+2 の形の式を作りたいです。 9k²+9k+4を3でくくると3(3k²+3k+1)+1 9k²+15k+8を3でくくると3(3k²+5k+2)+2 となぜなるんですか?4を3でくくると普通×3分の1で... 続きを読む

次式について 対偶「nが3の倍数でないならば、 hath+2は3の倍数でない」 nが3の倍数でないとき。 12 [REPEAT 数学Ⅰ 問題114] (1) の方が示しやすい。(代入しやすい) n は整数とする。次の命題を証明せよ。(10点)結論→対偶を利用 仮定²+n+2が3の倍数ならば,nは3の倍数である。 するといい 1次式について を証明すればよい。 kを整数とし、←人事 全ての数は、 3k,3k+1, k=0で0 1 ' 38+2 . 2 kを整数として、n=3k+1 k=1で3 4 5 または、n=3k+2 と表されるので、 k=2で6 7 8 (i) h=3k+1のとき、 n²+n+2 =(3+1)+(3k+1)+2 =9k2+9k+4 = 3(3R2+3R+1)+1← 3k2+3k+1は整数より、 hth+23の倍数でない。 (1) n=3k+2のとき(と 3の倍数3の倍数3の倍数 である でない でない 整数 3x+ の形 4k+1 ※同じように 40 5の 60 44k 倍数 5k 倍数 6k 倍数 4k+25k+2 5k+1 6k+1 6k+2 整数 hath+2 =(3k+2)+(3k+2)+2 同 3x+2 4k+3 15k+3 16k+3 =9k²+15k+8 =3(3k²+5k+2)+25 の形 4の倍数 5k+4 6RT4 でない 5の倍数 6k+5 対偶が真より でない 3k25k+2は整数より もとの命題も真 ++2、3の倍数でない。 と表せる。 6の倍数 でない

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英語 高校生

fについてです 解説が載っていなかったため質問しています、。 なぜ、③を選ぶことができるのでしょうか?

Long-s doctrin holds that we are protected from fungi not just by layered immune defenses but ( e ) we are mammals*, with core temperatures higher than fungi prefer. The cooler outer surfaces of our bodies are at risk of minor assaults-think of athlete's foot*, yeast infections, ringworm*-but in people with healthy immune systems, invasive* infections have been ( f ). That may have left us overconfident. "We have an enormous (g) spot," says Arturo Casadevall, a physician and molecular microbiologist at the Johns Hopkins Bloomberg School of Public Health. "Walk into the street and ask people what are they afraid of, and they'll tell you they're afraid of bacteria, they're afraid of viruses, but they don't fear dying of fungi." Ironically, it is our successes that made us vulnerable*. Fungi exploit damaged immune systems, but before the mid-20th century people with impaired immunity didn't live very long. Since then, medicine has gotten very good at keeping such people (h), even though their immune systems are compromised by illness or cancer treatment or age. It has also developed an array of therapies that deliberately suppress immunity, to keep transplant recipients healthy and treat autoimmune* disorders such as lupus* and rheumatoid arthritis*. ( i ) vast numbers of people are living now who are especially vulnerable to fungi. Not all of our vulnerability is the fault of medicine preserving life so successfully. Other ( j ) actions have opened more doors between the fungal world and our own. We clear land for crops and settlement and perturb* what were stable balances between fungi and their hosts. We carry goods and animals across the world, and fungi hitchhike on them. We drench crops in fungicides* and enhance the resistance of organisms residing nearby. (s) ELSE

解決済み 回答数: 1