Algebra Equazioni di secondo grado equazioni monomie 1 𝑥𝑥 2 = 0 3𝑥𝑥 2 = 0 4𝑥𝑥 2 = 0 10𝑥𝑥 2 = 0 2 2 𝑥𝑥 = 0 3 5 2 𝑥𝑥 = 0 7 2 3 4 𝑥𝑥 2 − 1 = 0 𝑥𝑥1 = −1, 𝑥𝑥2 = 1 𝑥𝑥 2 + 1 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 3𝑥𝑥 2 − 27 = 0 5 6 3𝑥𝑥 2 − 1 = 0 7 125𝑥𝑥 2 − 5 = 0 8 9 10 11 12 13 14 15 16 17 18 19 equazioni pure 𝑥𝑥 2 − √2 = 0 7 2 𝑥𝑥 − 1 = 0 8 7 + 49𝑥𝑥 2 = 0 5𝑥𝑥 2 = 1 𝑥𝑥 2 − 𝑥𝑥 = 0 7 2 𝑥𝑥 − 𝑥𝑥 = 0 9 2 𝑥𝑥 2 + 𝑥𝑥 = 0 3 81 2 9 𝑥𝑥 − 𝑥𝑥 = 0 4 2 𝑥𝑥 − 2𝑥𝑥 2 = 0 3 2 𝑥𝑥 + 𝑥𝑥 = 0 5 5𝑥𝑥 = 5𝑥𝑥 2 v 3.0 √3 √3 , 𝑥𝑥 = 3 2 3 1 1 𝑥𝑥1 = − , 𝑥𝑥2 = 5 5 4 4 𝑥𝑥1 = − √2, 𝑥𝑥2 = √2 𝑥𝑥1 = − 2√14 2√14 , 𝑥𝑥2 = 7 7 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥1 = − 𝑥𝑥1 = −2, 𝑥𝑥2 = 2 𝑥𝑥 2 + 9 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 9𝑥𝑥 2 − 4 = 0 𝑥𝑥1 = −3, 𝑥𝑥2 = 3 𝑥𝑥1 = − 𝑥𝑥 2 − 4 = 0 √5 √5 , 𝑥𝑥2 = 5 5 5𝑥𝑥 2 + 125 = 0 4 + 124𝑥𝑥 2 = 0 √3𝑥𝑥 2 + 1 = 0 4 2 𝑥𝑥 − 49 = 0 5 7 − 49𝑥𝑥 2 = 0 7 = −3𝑥𝑥 2 2 2 𝑥𝑥1 = − , 𝑥𝑥2 = 3 3 ∄𝑥𝑥 ∈ 𝑅𝑅 ∄ 𝑥𝑥 ∈ 𝑅𝑅 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥1 = − 𝑥𝑥1 = − 7√5 7√5 , 𝑥𝑥2 = 2 2 √7 √7 , 𝑥𝑥2 = 7 7 ∄ 𝑥𝑥 ∈ 𝑅𝑅 equazioni spurie 𝑥𝑥1 = 0, 𝑥𝑥2 = 1 𝑥𝑥1 = 0, 𝑥𝑥2 = 9 7 𝑥𝑥1 = 0, 𝑥𝑥2 = − 𝑥𝑥1 = 0, 𝑥𝑥2 = 𝑥𝑥1 = 0, x2 = 2 9 1 2 𝑥𝑥1 = 0, 𝑥𝑥2 = − 𝑥𝑥1 = 0, x2 = 1 2 3 5 3 5 3 3𝑥𝑥 2 + 5𝑥𝑥 = 0 𝑥𝑥1 = 0, 𝑥𝑥2 = − 5𝑥𝑥 2 + 10𝑥𝑥 = 0 𝑥𝑥1 = 0, 𝑥𝑥2 = −2 𝑥𝑥 2 + 4𝑥𝑥 = 0 9 2 2 𝑥𝑥 − 𝑥𝑥 = 0 4 3 2𝑥𝑥 + 𝑥𝑥 2 = 0 25 2 𝑥𝑥 + 𝑥𝑥 = 0 49 5𝑥𝑥 − 3𝑥𝑥 2 = 0 © 2016 - www.matematika.it 𝑥𝑥1 = 0, x2 = −4 𝑥𝑥1 = 0, 𝑥𝑥2 = 8 27 𝑥𝑥1 = 0, 𝑥𝑥2 = −2 𝑥𝑥1 = 0, 𝑥𝑥2 = − 𝑥𝑥1 = 0, 𝑥𝑥2 = 5 3 49 25 1 di 6 Algebra 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 𝑥𝑥 2 = √5𝑥𝑥 Equazioni di secondo grado 𝑥𝑥1 = 0, 𝑥𝑥2 = √5 √2𝑥𝑥 2 = −2𝑥𝑥 𝑥𝑥1 = 0, 𝑥𝑥2 = −√2 equazioni complete 𝑥𝑥 2 − 7𝑥𝑥 + 10 = 0 𝑥𝑥1 = 2, 𝑥𝑥2 = 5 𝑥𝑥 2 + 5𝑥𝑥 + 6 = 0 𝑥𝑥1 = −3, 𝑥𝑥2 = −2 𝑥𝑥 2 + 2𝑥𝑥 − 3 = 0 𝑥𝑥1 = −3, 𝑥𝑥2 = 1 2𝑥𝑥 2 + 7𝑥𝑥 + 3 = 0 𝑥𝑥1 = −3, 𝑥𝑥2 = − 𝑥𝑥 2 + 𝑥𝑥 + 12 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 2𝑥𝑥 2 + 5𝑥𝑥 − 12 = 0 𝑥𝑥1 = −4, 𝑥𝑥2 = 8 𝑥𝑥1 = − , 𝑥𝑥2 = 2 5 5𝑥𝑥 2 − 2x − 16 = 0 25𝑥𝑥 2 − 20𝑥𝑥 + 4 = 0 𝑥𝑥1 = 𝑥𝑥2 = 𝑥𝑥 2 − 5𝑥𝑥 + 6 = 0 2 5 3 2 𝑥𝑥1 = 2, 𝑥𝑥2 = 3 𝑥𝑥 2 + 𝑥𝑥 − 12 = 0 𝑥𝑥1 = −4, 𝑥𝑥2 = 3 𝑥𝑥 2 + 7𝑥𝑥 − 8 = 0 𝑥𝑥1 = −8, 𝑥𝑥2 = 1 9𝑥𝑥 2 − 6𝑥𝑥 + 1 = 0 𝑥𝑥1 = 𝑥𝑥2 = 𝑥𝑥 2 − 𝑥𝑥 = 20 1 3 𝑥𝑥1 = −4, 𝑥𝑥2 = 5 3𝑥𝑥 2 + 5𝑥𝑥 + 3 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥 2 = 𝑥𝑥 + 2 𝑥𝑥1 = −1, 𝑥𝑥2 = 2 1 𝑥𝑥1 = − , 𝑥𝑥2 = 2 2 2𝑥𝑥 2 = 3𝑥𝑥 + 2 v 3.0 1 2 © 2016 - www.matematika.it 2 di 6 Equazioni di secondo grado Algebra 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 10 = 3𝑥𝑥 2 + 𝑥𝑥 𝑥𝑥1 = −2, 𝑥𝑥2 = 5 3 𝑥𝑥 2 − 3√2𝑥𝑥 + 4 = 0 𝑥𝑥1 = √2, 𝑥𝑥2 = 2√2 4𝑥𝑥 2 − 4𝑥𝑥 − 1 = 0 𝑥𝑥1 = 3𝑥𝑥 2 − 𝑥𝑥 + 1 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥 2 + 4𝑥𝑥 + 1 = 0 𝑥𝑥1 = −2 − √3, 𝑥𝑥2 = −2 + √3 𝑥𝑥 2 = −𝑥𝑥 − 2 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥 2 − �√3 + √2�𝑥𝑥 + √6 = 0 𝑥𝑥1 = √2, 𝑥𝑥2 = √3 (2𝑥𝑥 + 1)2 − (𝑥𝑥 − 3)2 = 0 𝑥𝑥1 = −4, 𝑥𝑥2 = 𝑥𝑥 = (𝑥𝑥 + 2)2 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥 2 + �√2 − √3�𝑥𝑥 − √6 = 0 𝑥𝑥1 = 1 1 1 + 𝑥𝑥 = − 2 6 4 𝑥𝑥1 = 𝑥𝑥 2 + 16 = 6√2𝑥𝑥 −9 − 3√5 −9 + 3√5 , 𝑥𝑥2 = 2 2 −1 − √37 −1 + √37 , 𝑥𝑥2 = 12 12 𝑥𝑥1 = 2√2, 𝑥𝑥2 = 4√2 4√5𝑥𝑥 − 1 = 4𝑥𝑥 2 𝑥𝑥1 = 𝑥𝑥 2 − 4√3𝑥𝑥 + 12 = 0 √5 − 2 √5 + 2 , 𝑥𝑥2 = 2 2 𝑥𝑥1 = 𝑥𝑥2 = 2√3 𝑥𝑥 + √5 = �2𝑥𝑥 − √5��𝑥𝑥 + √5� 𝑥𝑥1 = −√5, 𝑥𝑥2 = 2 1 2 3 �𝑥𝑥 + � = � − 2𝑥𝑥� 2 2 𝑥𝑥1 = 2, 𝑥𝑥2 = 𝑥𝑥�𝑥𝑥 + √7� = 14 v 3.0 2 3 𝑥𝑥1 = −√2, 𝑥𝑥2 = √3 𝑥𝑥2 + 3𝑥𝑥1 + 3 = 0 3 𝑥𝑥 2 − 1 − √2 1 + √2 , 𝑥𝑥2 = 2 2 1 3 1 + √5 2 𝑥𝑥1 = −2√7, 𝑥𝑥2 = √7 © 2016 - www.matematika.it 3 di 6 Equazioni di secondo grado Algebra 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 1 𝑥𝑥 2 − 1 2 (3 − 𝑥𝑥) + − =0 3 6 3 2√3𝑥𝑥 = 𝑥𝑥 2 + 2 𝑥𝑥1 = 𝑥𝑥2 = 1 𝑥𝑥1 = √3 − 1, 𝑥𝑥2 = √3 + 1 equazioni di secondo grado frazionarie 2 𝑥𝑥 = 𝑥𝑥 2 𝑥𝑥1 = −2, 𝑥𝑥2 = 2 𝑥𝑥 √3 = 𝑥𝑥 √27 𝑥𝑥1 = −3, 𝑥𝑥2 = 3 𝑥𝑥 = 1 𝑥𝑥 𝑥𝑥 − 1 = − 𝑥𝑥1 = −1, 𝑥𝑥2 = 1 9 𝑥𝑥 − 1 𝑥𝑥1 = −2, 𝑥𝑥2 = 4 2 1 = 2 𝑥𝑥 + 3 𝑥𝑥 ∄ 𝑥𝑥 ∈ 𝑅𝑅 1 2 = 𝑥𝑥 2 𝑥𝑥 + 3 𝑥𝑥1 = −1, 𝑥𝑥2 = 2 1 − 𝑥𝑥 2 = 𝑥𝑥 2 + 1 𝑥𝑥 2 + 1 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 3 2𝑥𝑥 = 𝑥𝑥 − 1 𝑥𝑥 + 1 𝑥𝑥1 = − 3 4𝑥𝑥 − 2 = 𝑥𝑥(𝑥𝑥 − 2) 𝑥𝑥 𝑥𝑥1 = 4 1 1 + 𝑥𝑥 𝑥𝑥 + = − 3 𝑥𝑥 − 1 𝑥𝑥 − 1 𝑥𝑥 + 1 1 , 𝑥𝑥 = 3 2 2 5 − √21 5 + √21 , 𝑥𝑥2 = 4 4 1 𝑥𝑥1 = − , 𝑥𝑥2 = 2 2 1 2 − 𝑥𝑥 = 2 𝑥𝑥 𝑥𝑥 𝑥𝑥1 = 𝑥𝑥2 = 1 𝑥𝑥 + 3 1 1 − 2=− 𝑥𝑥 𝑥𝑥 𝑥𝑥 𝑥𝑥1 = −2 − √5 , 𝑥𝑥2 = −2 + √5 3𝑥𝑥 𝑥𝑥 2 2𝑥𝑥 + 2 = 𝑥𝑥 + 1 2𝑥𝑥 + 𝑥𝑥 − 1 1 − 2𝑥𝑥 𝑥𝑥1 = 0, 𝑥𝑥2 = 11 − 3𝑥𝑥 1 + 𝑥𝑥 1 = 2 − 4(𝑥𝑥 − 1) 𝑥𝑥 − 1 𝑥𝑥 + 1 1 9 1 𝑥𝑥1 = − , 𝑥𝑥2 = 3 3 1 𝑥𝑥 + 1 1 − 𝑥𝑥 + = 𝑥𝑥 2 − 1 𝑥𝑥 − 1 𝑥𝑥 + 1 ∄ 𝑥𝑥 ∈ 𝑅𝑅 2 𝑥𝑥 8 + = 𝑥𝑥 + 1 1 − 𝑥𝑥 1 − 𝑥𝑥 2 v 3.0 3 2 𝑥𝑥1 = −2, 𝑥𝑥2 = 3 © 2016 - www.matematika.it 4 di 6 Equazioni di secondo grado Algebra 73 74 75 3𝑥𝑥 + 2 1 𝑥𝑥 + 1 + = 𝑥𝑥 2 + 2𝑥𝑥 𝑥𝑥 𝑥𝑥 + 2 𝑥𝑥1 = −1, 𝑥𝑥2 = 4 𝑥𝑥 2 − 11 𝑥𝑥 𝑥𝑥 + 1 + = 2 𝑥𝑥 + 2𝑥𝑥 − 3 𝑥𝑥 − 1 𝑥𝑥 + 3 𝑥𝑥1 = −5, 𝑥𝑥2 = 2 2 2𝑥𝑥 2 − 𝑥𝑥 − = 𝑥𝑥 𝑥𝑥 + 1 𝑥𝑥 𝑥𝑥1 = 1, 𝑥𝑥2 = 0 𝑛𝑛𝑛𝑛𝑛𝑛 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 equazioni di secondo grado di vario tipo 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 4𝑥𝑥(2 − 𝑥𝑥) + (𝑥𝑥 − 2) = −11 𝑥𝑥1 = −3, 𝑥𝑥2 = 3 𝑥𝑥�𝑥𝑥 + √7� = 14 𝑥𝑥1 = −2√7, 𝑥𝑥2 = √7 1 (𝑥𝑥 − 1) + 𝑥𝑥 = (𝑥𝑥 + 1)(𝑥𝑥 − 2) 2 1 𝑥𝑥1 = − , 𝑥𝑥2 = 3 2 2 �√3 − 2𝑥𝑥� = �𝑥𝑥 + √3� 2 𝑥𝑥1 = 0, 𝑥𝑥2 = 2√3 4 + (1 + 2𝑥𝑥)2 = 0 ∄ 𝑥𝑥 ∈ 𝑅𝑅 (2𝑥𝑥 − 1)2 + 4(𝑥𝑥 − 2)(𝑥𝑥 + 2) = −18 ∄ 𝑥𝑥 ∈ 𝑅𝑅 1 𝑥𝑥 2 − 1 2 (3 − 𝑥𝑥) + − =0 3 6 3 2 𝑥𝑥1 = 𝑥𝑥2 = 1 √2(2𝑥𝑥 + 1) + �𝑥𝑥 − √2� = 𝑥𝑥 + 4 𝑥𝑥1 = 1 − √2, 𝑥𝑥2 = √2 1 1 1 + = 𝑥𝑥 + 1 12 1 − 𝑥𝑥 𝑥𝑥1 = −12 − √145, 𝑥𝑥2 = −12 + √145 2√3𝑥𝑥 = 𝑥𝑥 2 + 2 1 𝑥𝑥 + √3 + 𝑥𝑥 + 2 = 1 𝑥𝑥 − √3 =3 𝑥𝑥1 = 6 +1 𝑥𝑥 + 2 1 − 2√7 1 + 2√7 , 𝑥𝑥2 = 3 3 𝑥𝑥1 = −4, 𝑥𝑥 − 5 𝑥𝑥 5 − = 8 5 𝑥𝑥 − 10 𝑥𝑥1 = − 1 4 − 𝑥𝑥 2 − = 𝑥𝑥(2 − 𝑥𝑥) 𝑥𝑥(𝑥𝑥 + 2) 4 − 𝑥𝑥 2 10 , 3 𝑥𝑥2 = 1 𝑥𝑥2 = 5 𝑥𝑥1 = 2 𝑛𝑛𝑛𝑛𝑛𝑛 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎, 𝑥𝑥2 = 3 1 1 1 − = 𝑥𝑥(𝑥𝑥 + 3) 𝑥𝑥(2 − 𝑥𝑥) 6𝑥𝑥 v 3.0 𝑥𝑥1 = √3 − 1, 𝑥𝑥2 = √3 + 1 𝑥𝑥1 = −1, © 2016 - www.matematika.it 𝑥𝑥2 = 12 5 di 6 Equazioni di secondo grado Algebra 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 𝑥𝑥 + 2 (2 + 3𝑥𝑥) 4 − = 1+ 2 𝑥𝑥 2(4 − 3𝑥𝑥) 3𝑥𝑥 − 4𝑥𝑥 𝑥𝑥1 = −6, 𝑥𝑥 1 𝑥𝑥 𝑥𝑥 + 6 − = + 𝑥𝑥 − 6 2 6 6 − 𝑥𝑥 𝑥𝑥1 = −3, 1 1 1 − = 3𝑥𝑥 − 𝑥𝑥 2 6𝑥𝑥 2𝑥𝑥 − 𝑥𝑥 2 ∄ 𝑥𝑥 ∈ 𝑅𝑅 5 9 𝑥𝑥 − 3 − = 4𝑥𝑥 4 𝑥𝑥 + 1 𝑥𝑥1 = − 4 3𝑥𝑥 +3= 2 (𝑥𝑥 − 2) 2 − 𝑥𝑥 ∄ 𝑥𝑥 ∈ 𝑅𝑅 𝑥𝑥 − √3 5 , 13 𝑥𝑥2 = 4 𝑛𝑛𝑛𝑛𝑛𝑛 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 3 𝑥𝑥2 = 1 𝑥𝑥2 = 18 2√3 𝑥𝑥 − 2 3𝑥𝑥 − 1 𝑥𝑥√3 + 1 𝑥𝑥1 = − 5 1 3𝑥𝑥 + 2 + = 2 2𝑥𝑥 + 2 2𝑥𝑥 − 2 𝑥𝑥 + 𝑥𝑥 + 1 𝑥𝑥1 = 0, 2 1 1 1 2 − �𝑥𝑥 − � �𝑥𝑥 − � + �𝑥𝑥 − � =0 (𝑥𝑥 − 1)2 𝑥𝑥 − 1 𝑥𝑥 + 1 𝑥𝑥 − 1 𝑥𝑥1 = 1 − √3, 𝑥𝑥2 = 1 + √3 𝑥𝑥√3 − 1 = 4 3 5 − 2= 2 (𝑥𝑥 − 2) 𝑥𝑥 4𝑥𝑥 − 2𝑥𝑥 2 𝑥𝑥1 = √3 , 𝑥𝑥 = √3 2 2 −7 − √217 , 7 𝑥𝑥2 = 𝑥𝑥2 = 4 5 1 5 − 2 = 6 + 2𝑥𝑥 𝑥𝑥 − 3𝑥𝑥 9 − 𝑥𝑥 2 3 𝑥𝑥1 = − , 5 1 1 2 1 − = + 𝑥𝑥 − 5 4 − 𝑥𝑥 𝑥𝑥 − 4 𝑥𝑥 − 3 𝑥𝑥1 = 5 − √2, 𝑥𝑥2 = 5 + √2 𝑥𝑥 2 1 = 2 200 − 𝑥𝑥 7 𝑥𝑥1 = −5, 𝑥𝑥 + 3 𝑥𝑥 + 5 2𝑥𝑥 + 2 + = 𝑥𝑥 + 1 𝑥𝑥 + 2 𝑥𝑥 4 𝑥𝑥1 = − , 3 2(𝑥𝑥 − 1) (𝑥𝑥 + 1) + =3 𝑥𝑥 + 1 4(𝑥𝑥 − 1) 𝑥𝑥1 = 𝑥𝑥 − 2 2𝑥𝑥 + 9 2𝑥𝑥 + 1 + = 3 − 𝑥𝑥 𝑥𝑥 2 − 9 𝑥𝑥 + 3 𝑥𝑥2 = 2 𝑥𝑥2 = 1 𝑥𝑥2 = 5 −7 − 4√7 −7 + 4√7 , 𝑥𝑥2 = 3 3 𝑥𝑥1 = 1 − √7, 𝑥𝑥2 = 1 + √7 5𝑥𝑥 2 − 5𝑥𝑥 − 28 4 2 = − 𝑥𝑥 2 − 𝑥𝑥 − 6 𝑥𝑥 + 2 𝑥𝑥 − 3 v 3.0 −7 + √217 7 𝑥𝑥1 = −1, © 2016 - www.matematika.it 𝑥𝑥2 = 12 5 6 di 6