Question

Urgent!!

1. f(x)= x^2+x-2

2. f(x)= x^2+2x-3

3. f(x)= x^2+3x-4

4. f(x)= x^2+x-6

5. f(x)= x^2+4x-5

6. f(x)= x^2+2x-8

7. f(x)= x^2-x-2

8. f(x)= x^2+3x-10

9. f(x)= x^2-2x-3

10. f(x)= x^2-x-6

11. f(x)= x^2+x-12

12. f(x)= x^2-3x-4

13. f(x)= x^2-2x-8

14. f(x)= x^2-x-12

15. f(x)= x^2+x-20

Answer 1

Răspuns:

Cand le rezolvi, mai intai sa le egalezi cu 0 pe fiecare in parte.

La 15:f(x)=x^2+x-20=0

(a=1,b=1,c=-20)

delta=1^2-4*1*(-20)=1+80=81

x1=$\frac{-b+\sqrt{81} \\}{2}$=$\frac{-1+9}{2}=4$

x2=$\frac{-b-\sqrt{81} \\}{2}$=$\frac{-1-9}{2}=-5$

Explicație pas cu pas: