与えられた多項式AとBに対して、A+BとA-Bをそれぞれ計算する問題です。代数学多項式加減算式の計算2025/4/161. 問題の内容与えられた多項式AとBに対して、A+BとA-Bをそれぞれ計算する問題です。2. 解き方の手順(1)A = 2x2+3x−12x^2 + 3x - 12x2+3x−1, B = 4x2−5x−64x^2 - 5x - 64x2−5x−6A+B = (2x2+3x−1)+(4x2−5x−6)(2x^2 + 3x - 1) + (4x^2 - 5x - 6)(2x2+3x−1)+(4x2−5x−6)= 2x2+4x2+3x−5x−1−62x^2 + 4x^2 + 3x - 5x - 1 - 62x2+4x2+3x−5x−1−6= 6x2−2x−76x^2 - 2x - 76x2−2x−7A-B = (2x2+3x−1)−(4x2−5x−6)(2x^2 + 3x - 1) - (4x^2 - 5x - 6)(2x2+3x−1)−(4x2−5x−6)= 2x2+3x−1−4x2+5x+62x^2 + 3x - 1 - 4x^2 + 5x + 62x2+3x−1−4x2+5x+6= 2x2−4x2+3x+5x−1+62x^2 - 4x^2 + 3x + 5x - 1 + 62x2−4x2+3x+5x−1+6= −2x2+8x+5-2x^2 + 8x + 5−2x2+8x+5(2)A = 4x3−3x2−2x+54x^3 - 3x^2 - 2x + 54x3−3x2−2x+5, B = 2x3−3x2+72x^3 - 3x^2 + 72x3−3x2+7A+B = (4x3−3x2−2x+5)+(2x3−3x2+7)(4x^3 - 3x^2 - 2x + 5) + (2x^3 - 3x^2 + 7)(4x3−3x2−2x+5)+(2x3−3x2+7)= 4x3+2x3−3x2−3x2−2x+5+74x^3 + 2x^3 - 3x^2 - 3x^2 - 2x + 5 + 74x3+2x3−3x2−3x2−2x+5+7= 6x3−6x2−2x+126x^3 - 6x^2 - 2x + 126x3−6x2−2x+12A-B = (4x3−3x2−2x+5)−(2x3−3x2+7)(4x^3 - 3x^2 - 2x + 5) - (2x^3 - 3x^2 + 7)(4x3−3x2−2x+5)−(2x3−3x2+7)= 4x3−3x2−2x+5−2x3+3x2−74x^3 - 3x^2 - 2x + 5 - 2x^3 + 3x^2 - 74x3−3x2−2x+5−2x3+3x2−7= 4x3−2x3−3x2+3x2−2x+5−74x^3 - 2x^3 - 3x^2 + 3x^2 - 2x + 5 - 74x3−2x3−3x2+3x2−2x+5−7= 2x3−2x−22x^3 - 2x - 22x3−2x−23. 最終的な答え(1)A+B = 6x2−2x−76x^2 - 2x - 76x2−2x−7A-B = −2x2+8x+5-2x^2 + 8x + 5−2x2+8x+5(2)A+B = 6x3−6x2−2x+126x^3 - 6x^2 - 2x + 126x3−6x2−2x+12A-B = 2x3−2x−22x^3 - 2x - 22x3−2x−2