L ON TAP CHUONG THEO TOAN BO NOI DUNG SAU Cac kien thurc trong chuong
11. MOT SO CAU HOI TRAC NGHIEM ON TAP CHUONG
Chgn cau tra Idi diing trong cac bai tap sau 1. f(x) = x^ + (m + 2)x + m
(a) f(x) = 0 cd nghiem Vm; (c) f(x) = 0 cd nghiem kep Vm;
Trd Idi. Chgn (a).
(b) f(x) = 0 vd nghiem Vm; (d) ca ba cau tren deu sai.
2. f(x) = x ^ - 2 ( m + l ) x + m - 5
(a) f(x) vd nghiem Vm; (b) f(x) cd nghiem kep Vm; (c) f(x) cd nghiem Vm; (d) ca ba cau tren deu sai.
Trd Idi. Chgn (c).
3. f(x) = x^+ V 3 x - m ^ - l
(a) f(x) vd nghiem Vm; (b) f(x) cd nghiem Vm; (c) f(x) cd nghiem kep Vm; (d) ca ba cau tren deu sai.
Trd Idi. Chgn (b).
4. f(x) = (2m^ + 2)x^ - 2mx +1
(a) f(x) vd nghiem Vm; (b) f(x) cd nghiem Vm; (c) f(x) cd nghiem kep Vm; (d) ca ba cau tren deu sai.
Trd Idi. Chgn (a).
X^ 2
5. f(x) = — + (m + l)x + m + 2
(a) f(x) cd nghiem Vm; (b) f(x) cd nghiem kep Vm; (c) f(x) vd nghiem Vm; (d) ca ba cau tren deu sai.
Trd Idi. Chgn (c).
6. f(x) = x^ - 2(m - 2)x + 3m^ - 5m + 12
(a) f(x) cd nghiem Vm; (b) f(x) vd nghiem Vm; (c) f(x) cd nghiem kep Vm; (d) ca ba cau tren deu sai.
Trd Idi. Chgn (b).
7. f(x) = x ^ - ( V 3 m + l)x + m ^ - V3m + 7
(a) f(x) CO 3 nghiem Vm; (b) f(x) cd 2 nghiem Vm; (c) f(x) vd nghiem Vm; (d) cd diing 1 nghiem Vm.
Trd Idi. Chgn (b).
8. f(x) = x +4x + m - l ludn ludn duong khi ( a ) m < 5 ; (b) m > 5;
(c)m = 5; (d)m = l.
Trd Idi. Chgn (a).
9. f(x) = -V2 X + 2x + m - 2 ludn ludn am khi 1
(a) m < 2; ( b ) m <
(c) m < 2 ^ ; (d) m > 2 1=
V2 V2
Trd Idi. Chgn (c).
10. f(x) = (3m + 2)x - (3m + 4)x + m + 1 ludn ludn duong khi
-2 + 2V7 (b) m < (b) m < -2 + 2V7 , 2 + 2V7 (a) m < hoac m > (c) m G 0 ; Trd Idi. Chgn (d).
11. Nghiem cua ba't phuong trinh x(x + 4) < (x^ + 2) la (a) X < 0 hoac x > 4; (d)m -2+2V7 2+2V7 1 (c) X < 4; (b) X < - ; 2 (d) X > i- 2 Trd lai. Chgn (b).
12. Nghiem ciia bat phuang trinh 2 ( x + l ) ^ - 4 3 > 3 x l a
(a) X > - 2 ; (c) X e 0 ;
(b) X < 4; (d) X e M
Trd Idi. Chgn (c).
13. Nghiem cua bat phuang trinh 2x + 5 3 ,. < la X - 5 x + 4 x - 1 (a)S = ( - ^ ; l ) ; (b) S = (9;+c»); (c)S = ( l ; 4 ) u ( 9 ; + a ) ) ; (d)S = (4;9). Trd Idi. Chgn (c).
14. Nghiem cua bat phuong trinh x^-6x + 7 x - 1 ,. x^+6x + 7 x + 1 ( a ) x < - l ; la 12 (b) X > — ; 10 (c)x>0; (d)x € (-o); l ) u Tra/^/. Chgn (d).
15. Tap xac dinh cua ham sd f(x) =
V - 5 ; 1-x 1-x X +X + 1 - 1 la (a) (-o); 0); (c) (-2; 0); Trd Idi. Chgn (c). (b) (-c»; -2); (d) R. . , [ x ' - 3 x + 4 < 0 . ^.„ ,^. 16. He bat phuong trinh vo nghiem khi.
( c ) m > l ; ( d ) m < 4 .
Trd Idi. Chgn (b).