Question

3x2+4x-39=0 4x2-3x-1=0 3x2+8x+5=0

Answer 1

3x^2+4x-39=0

D = 16 -4×3×(-39) = 16 + 468 = 484 > 0

x1 = -4+22 / 6 = 3

x2 = -4-22 / 6 = -26 / 6 = -4 2/6 = -4 1/3

Ответ: 3; -4 1/3.

4x^2-3x-1=0

D = 9 -4×4×(-1) = 9 + 16 = 25 > 0

x1 = 3+5 / 8 = 1

x2 = 3-5 / 8 = -2 / 8 = -1/4 = -0,25

Ответ: 1; -0,25.

3x^2+8x+5=0

D = 64 - 4×3×5 = 64 - 60 = 4 > 0

x1 = -8+2 / 6 = -1

x2 = -8-2 / 6 = -10/6 = -5/3 = - 1 2/3

Ответ: -1; -1 2/3.

Answer 2

Ответ:

1. -1; 6

2. 0,5; 1,75

3. 10; 11

Объяснение:

1. Дискриминант = 484, следовательно корень = 22

х1 = -1

х2 ≈ 6,3

2. Дискриминант = 25, следовательно корень = 5

х1 = 0,5

х2 = 1,75

3. Дискриминант = 4, следовательно корень = 2

х1 ≈ 10

х2 = 11

Answer 3

It looks like you've provided three quadratic equations. If you're looking for solutions to these equations, I can help you with that. Quadratic equations are typically solved using various methods, such as factoring, the quadratic formula, or completing the square. Let's solve each equation one by one:

1. 3x^2 + 4x - 39 = 0: To solve this equation, we can use the quadratic formula: x = (-b ± √(b² - 4ac)) / 2a. Here, a = 3, b = 4, and c = -39.

   Plugging these values into the formula: x = (-4 ± √(4² - 4 * 3 * (-39))) / (2 * 3) x = (-4 ± √(16 + 468)) / 6 x = (-4 ± √484) / 6 x = (-4 ± 22) / 6

   So, the solutions are: x = (18) / 6 = 3 x = (-26) / 6 = -13/3

2. 4x^2 - 3x - 1 = 0: We'll use the quadratic formula again. Here, a = 4, b = -3, and c = -1.

   Plugging these values into the formula: x = (3 ± √((-3)² - 4 * 4 * (-1))) / (2 * 4) x = (3 ± √(9 + 16)) / 8 x = (3 ± √25) / 8

   So, the solutions are: x = (3 + 5) / 8 = 8/8 = 1 x = (3 - 5) / 8 = -2/8 = -1/4

3. 3x^2 + 8x + 5 = 0: Again, using the quadratic formula with a = 3, b = 8, and c = 5:

   x = (-8 ± √(8² - 4 * 3 * 5)) / (2 * 3) x = (-8 ± √(64 - 60)) / 6 x = (-8 ± √4) / 6

   So, the solutions are: x = (-8 + 2) / 6 = -1 x = (-8 - 2) / 6 = -5/3

Those are the solutions for the given quadratic equations.