Question

Решите неравенство: 4х^2-225 меньше или равно нулю

Answer 1

4х^2-225<=0

(2X-15)(2X+15)<=0

(X-15/2)(X+15/2)<=0

[-15/12;15/12]

Answer 2

4x^2=225

x^2=225:4=56.25

х=7.5