求10道一元二次方程练习题及答案,感激不尽!!!,谁能给我100道一元二次方程计算题

发布时间:2020-07-11 05:56:47

求10道一元二次方程练习题及答案,感激不尽!!!,谁能给我100道一元二次方程计算题

网友回答

1)(3x+1)^2=7
  解:(3x+1)^2=7 ∴(3x+1)^2=7 ∴3x+1=±√7(注意不要丢解) ∴x= (±√7-1)/3
  (2)9x^2-24x+16=11
  解: 9x^2-24x+16=11 ∴(3x-4)^2=11 ∴3x-4=±√11 ∴x= (±√11+4)/3 ∴原方程的解为x1=(√11+4)/3 x2=(-√11+4)/3
  (3) (x+3)(x-6)=-8
  解:(x+3)(x-6)=-8 化简整理得 x^2-3x-10=0 (方程左边为二次三项式,右边为零) (x-5)(x+2)=0 (方程左边分解因式) ∴x-5=0或x+2=0 (转化成两个一元一次方程) ∴x1=5,x2=-2是原方程的解。
  (4) 2x^2+3x=0
  解:2x^2+3x=0 x(2x+3)=0 (用提公因式法将方程左边分解因式) ∴x=0或2x+3=0 (转化成两个一元一次方程) ∴x1=0,x2=-3/2是原方程的解。 注意:有些同学做这种题目时容易丢掉x=0这个解,应记住一元二次方程有两个解。
  (5) 6x^2+5x-50=0 (选学)
   解:6x2+5x-50=0 (2x-5)(3x+10)=0 (十字相乘分解因式时要特别注意符号不要出错) ∴2x-5=0或3x+10=0 ∴x1=5/2, x2=-10/3 是原方程的解。
  (6)x^2-4x+4=0 (选学)
  解:x^2-4x+4 =0 (∵4 可分解为2 ·2 ,∴此题可用因式分解法) (x-2)(x-2 )=0 ∴x1=2 ,x2=2是原方程的解。
  (7)(x-2)^2=4(2x+3)^2
  解.(x-2)^2-4(2x+3)^2=0. [x-2+2(2x+3)][(x-2-2(2x+3)=0.
   (5x+4)(-5x-8)=0.
   x1=-4/5, x2=-8/5
  (8)y^2+2√2y-4=0
  解(y+√2)^2-2-4=0.
   (y+ √2)^2=6.
   y+√2=√6.
   y=-√2±√6.
   y1=-√2+√6;
   y2=-√2-√6.
  (9)(x+1)^2-3(x+1)+2=0
  解(x+1-1)(x+1-2)=0.
   x(x-1)=0.
   x1=0,
   x2=1.
  (10)x^2+2ax-3a^2=0(a为常数)
  解 (x+3a)(x-a)=0.
   x1=-3a,
   x2=a.

网友回答

(1)x^2-9x+8=0 答案:x1=8 x2=1
  (2)x^2+6x-27=0 答案:x1=3 x2=-9
  (3)x^2-2x-80=0 答案:x1=-8 x2=10
  (4)x^2+10x-200=0 答案:x1=-20 x2=10
  (5)x^2-20x+96=0 答案:x1=12 x2=8
  (6)x^2+23x+76=0 答案:x1=-19 x2=-4
  (7)x^2-25x+154=0 答案:x1=14 x2=11
  (8)x^2-12x-108=0 答案:x1=-6 x2=18
  (9)x^2+4x-252=0 答案:x1=14 x2=-18
  (10)x^2-11x-102=0 答案:x1=17 x2=-6
  (11)x^2+15x-54=0 答案:x1=-18 x2=3
  (12)x^2+11x+18=0 答案:x1=-2 x2=-9
  (13)x^2-9x+20=0 答案:x1=4 x2=5
  (14)x^2+19x+90=0 答案:x1=-10 x2=-9
  (15)x^2-25x+156=0 答案:x1=13 x2=12
  (16)x^2-22x+57=0 答案:x1=3 x2=19
  (17)x^2-5x-176=0 答案:x1=16 x2=-11
  (18)x^2-26x+133=0 答案:x1=7 x2=19
  (19)x^2+10x-11=0 答案:x1=-11 x2=1
  (20)x^2-3x-304=0 答案:x1=-16 x2=19
  (21)x^2+13x-140=0 答案:x1=7 x2=-20
  (22)x^2+13x-48=0 答案:x1=3 x2=-16
  (23)x^2+5x-176=0 答案:x1=-16 x2=11
  (24)x^2+28x+171=0 答案:x1=-9 x2=-19
  (25)x^2+14x+45=0 答案:x1=-9 x2=-5
  (26)x^2-9x-136=0 答案:x1=-8 x2=17
  (27)x^2-15x-76=0 答案:x1=19 x2=-4
  (28)x^2+23x+126=0 答案:x1=-9 x2=-14
  (29)x^2+9x-70=0 答案:x1=-14 x2=5
  (30)x^2-1x-56=0 答案:x1=8 x2=-7
  (31)x^2+7x-60=0 答案:x1=5 x2=-12
  (32)x^2+10x-39=0 答案:x1=-13 x2=3
  (33)x^2+19x+34=0 答案:x1=-17 x2=-2
  (34)x^2-6x-160=0 答案:x1=16 x2=-10
  (35)x^2-6x-55=0 答案:x1=11 x2=-5
  (36)x^2-7x-144=0 答案:x1=-9 x2=16
  (37)x^2+20x+51=0 答案:x1=-3 x2=-17
  (38)x^2-9x+14=0 答案:x1=2 x2=7
  (39)x^2-29x+208=0 答案:x1=16 x2=13
  (40)x^2+19x-20=0 答案:x1=-20 x2=1
  (41)x^2-13x-48=0 答案:x1=16 x2=-3
  (42)x^2+10x+24=0 答案:x1=-6 x2=-4
  (43)x^2+28x+180=0 答案:x1=-10 x2=-18
  (44)x^2-8x-209=0 答案:x1=-11 x2=19
  (45)x^2+23x+90=0 答案:x1=-18 x2=-5
  (46)x^2+7x+6=0 答案:x1=-6 x2=-1
  (47)x^2+16x+28=0 答案:x1=-14 x2=-2
  (48)x^2+5x-50=0 答案:x1=-10 x2=5
  (49)x^2+13x-14=0 答案:x1=1 x2=-14
  (50)x^2-23x+102=0 答案:x1=17 x2=6
  (51)x^2+5x-176=0 答案:x1=-16 x2=11
  (52)x^2-8x-20=0 答案:x1=-2 x2=10
  (53)x^2-16x+39=0 答案:x1=3 x2=13
  (54)x^2+32x+240=0 答案:x1=-20 x2=-12
  (55)x^2+34x+288=0 答案:x1=-18 x2=-16
  (56)x^2+22x+105=0 答案:x1=-7 x2=-15
  (57)x^2+19x-20=0 答案:x1=-20 x2=1
  (58)x^2-7x+6=0 答案:x1=6 x2=1
  (59)x^2+4x-221=0 答案:x1=13 x2=-17
  (60)x^2+6x-91=0 答案:x1=-13 x2=7
  (61)x^2+8x+12=0 答案:x1=-2 x2=-6
  (62)x^2+7x-120=0 答案:x1=-15 x2=8
  (63)x^2-18x+17=0 答案:x1=17 x2=1
  (64)x^2+7x-170=0 答案:x1=-17 x2=10
  (65)x^2+6x+8=0 答案:x1=-4 x2=-2
  (66)x^2+13x+12=0 答案:x1=-1 x2=-12
  (67)x^2+24x+119=0 答案:x1=-7 x2=-17
  (68)x^2+11x-42=0 答案:x1=3 x2=-14
  (69)x^20x-289=0 答案:x1=17 x2=-17
  (70)x^2+13x+30=0 答案:x1=-3 x2=-10
  (71)x^2-24x+140=0 答案:x1=14 x2=10
  (72)x^2+4x-60=0 答案:x1=-10 x2=6
  (73)x^2+27x+170=0 答案:x1=-10 x2=-17
  (74)x^2+27x+152=0 答案:x1=-19 x2=-8
  (75)x^2-2x-99=0 答案:x1=11 x2=-9
  (76)x^2+12x+11=0 答案:x1=-11 x2=-1
  (77)x^2+17x+70=0 答案:x1=-10 x2=-7
  (78)x^2+20x+19=0 答案:x1=-19 x2=-1
  (79)x^2-2x-168=0 答案:x1=-12 x2=14
  (80)x^2-13x+30=0 答案:x1=3 x2=10
  (81)x^2-10x-119=0 答案:x1=17 x2=-7
  (82)x^2+16x-17=0 答案:x1=1 x2=-17
  (83)x^2-1x-20=0 答案:x1=5 x2=-4
  (84)x^2-2x-288=0 答案:x1=18 x2=-16
  (85)x^2-20x+64=0 答案:x1=16 x2=4
  (86)x^2+22x+105=0 答案:x1=-7 x2=-15
  (87)x^2+13x+12=0 答案:x1=-1 x2=-12
  (88)x^2-4x-285=0 答案:x1=19 x2=-15
  (89)x^2+26x+133=0 答案:x1=-19 x2=-7
  (90)x^2-17x+16=0 答案:x1=1 x2=16
  (91)x^2+3x-4=0 答案:x1=1 x2=-4
  (92)x^2-14x+48=0 答案:x1=6 x2=8
  (93)x^2-12x-133=0 答案:x1=19 x2=-7
  (94)x^2+5x+4=0 答案:x1=-1 x2=-4
  (95)x^2+6x-91=0 答案:x1=7 x2=-13
  (96)x^2+3x-4=0 答案:x1=-4 x2=1
  (97)x^2-13x+12=0 答案:x1=12 x2=1
  (98)x^2+7x-44=0 答案:x1=-11 x2=4
  (99)x^2-6x-7=0 答案:x1=-1 x2=7
  (100)x^2-9x-90=0 答案:x1=15 x2=-6
  (101)x^2+17x+72=0 答案:x1=-8 x2=-9
  (102)x^2+13x-14=0 答案:x1=-14 x2=1
  (103)x^2+9x-36=0 答案:x1=-12 x2=3
  (104)x^2-9x-90=0 答案:x1=-6 x2=15
  (105)x^2+14x+13=0 答案:x1=-1 x2=-13
  (106)x^2-16x+63=0 答案:x1=7 x2=9
  (107)x^2-15x+44=0 答案:x1=4 x2=11
  (108)x^2+2x-168=0 答案:x1=-14 x2=12
  (109)x^2-6x-216=0 答案:x1=-12 x2=18
  (110)x^2-6x-55=0 答案:x1=11 x2=-5
  (111)x^2+18x+32=0 答案:x1=-2 x2=-16
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