Question

Функция задана формулой f(x)=2x^2+13x. При каких x f(x)=7.Запиши ответы в порядке возрастания

Answer 1

То что в скобке не пиши, это формула если ты не понял(а) как я решила

Answer 2

To find the values of x for which f(x) = 7, we need to solve the equation:

2x^2 + 13x = 7

Now, let's rearrange the equation to get it in the standard quadratic form:

2x^2 + 13x - 7 = 0

To solve this quadratic equation, we can either factor it or use the quadratic formula. In this case, let's use the quadratic formula:

The quadratic formula is given by: x = (-b ± √(b^2 - 4ac)) / 2a

For our equation, a = 2, b = 13, and c = -7. Plugging these values into the formula:

x = ( -13 ± √(13^2 - 4 * 2 * -7)) / 2 * 2

x = ( -13 ± √(169 + 56)) / 4

x = ( -13 ± √225) / 4

x = ( -13 ± 15) / 4

Now we get two possible values for x:

1. x = ( -13 + 15) / 4 = 2 / 4 = 1/2
2. x = ( -13 - 15) / 4 = -28 / 4 = -7

So, the two values of x for which f(x) = 7 are 1/2 and -7. Writing them in ascending order:

x = -7, 1/2