Rút gọn A

5 Cho
x 2
+
90
A
€
2
XC²²4
+
162-X² 2.
х:42
2
2=X
a) Rus
Jon A
b) Tim GT A biet 1x) =
l'im xc ete A CO
Jun
T
J
c)
d) Tim xe & Z do A nguyen
để
at J