Question

Rozwiąż równanie (x + 3/2)^2 cosx= |cosx|

Answer 1

(x+3/2)^2 cosx = |cosx|

 

(x+3/2)^2 (-cosx)= cosx      i           (x+3/2)^2 cosx= cosx

(x+3/2)^2 * (-1) = 1                         (x+3/2) ^2= 1

-x2 - 3x - 9/4 = 1                              x2 + 3x + 9/4 = 1

-x2 -3x -13/4 = 0                               x2+3x + 5/4=0

delta = 9 -13 = -4                                     delta= 9-5=4    pierwiastek z delty=2

delta<0                                                   x= -3-2 / 2 = -5/2

brak rozwiązania                                     x= -3+2 / 2 = -1/2