Kopertina e librit Matematika 12

Zgjidhja e ushtrimit 5

Zgjidhja e ushtrimit 5 të mësimit 1.4A në librin Matematika 12 nga shtëpia botuese Botime Pegi me autorë Brian Jefferson, David Bowles, Eddie Mullan, Garry Wiseman, John Rayneau, Katie Wood, Mike Heylings, Paul Williams dhe Rob Wagner.


Pyetja

Veçoni katrorin e binomit për të gjetur zgjidhjet e sakta për këto ekuacione të fuqisë së dytë.

  1. x22x=0x^2 - 2x = 0
  2. 34xx2=03 - 4x - x^2 = 0
  3. x214x+33=0x^2 - 14x + 33 = 0
  4. x2+8x+10=0x^2 + 8x + 10 = 0
  5. x26x+9=0x^2 - 6x + 9 = 0
  6. x2+10x+24=0x^2 + 10x + 24 = 0
  7. x2+22x+118=0x^2 + 22x + 118 = 0
  8. x216x+54=0x^2 - 16x + 54 = 0
  9. 4x212x+2=04x^2 - 12x + 2 = 0
  10. 9x2+12x2=09x^2 + 12x - 2 = 0
  11. x2+11x+3=0x^2 + 11x + 3 = 0
  12. 9x230x32=09x^2 - 30x - 32 = 0

Zgjidhja

  1. x22x=0x22x+11=0(x1)21=0(x1)2=1x1=1x1=±1x=1±1x=2x^2 - 2x = 0 \rArr x^2-2x+1-1=0 \rArr (x - 1)^2 - 1 = 0 \rArr (x - 1)^2 = 1 \rArr x-1=\sqrt{1} \rArr x - 1 = \pm 1 \rArr x = 1 \pm 1 \rArr x= 2 ose x=0x=0
  2. 34xx2=0(x2+4x3)=0(x2+4x+443)[(x+2)243]=0[(x+2)27]=0x+2=±7x=2±73 - 4x - x^2 = 0 \rArr -(x^2+4x-3) = 0 \rArr -(x^2+4x+4-4-3) \rArr -[(x + 2)^2 - 4 - 3] = 0 \rArr [(x + 2)^2 - 7] = 0 \rArr x + 2 = \pm \sqrt{7} \rArr x = -2 \pm \sqrt{7} \rArr x=72x=\sqrt7-2 ose x=27x=-2-\sqrt7
  3. x214x+33=0x214x+4949+33=0(x7)249+33=0(x7)216=0(x7)2=16x7=±4x=7±4x=7+4=11x^2 - 14x + 33 = 0 \rArr x^2-14x+49-49+33=0 \rArr (x - 7)^2 - 49 + 33 = 0 \rArr (x - 7)^2 - 16 = 0 \rArr (x-7)^2=16 \rArr x - 7 = \pm 4 \rArr x = 7 \pm 4 \rArr x=7+4 = 11 ose x=74=3x=7-4 =3
  4. x2+8x+10=0x2+8x+1616+10=0(x+4)216+10=0(x+4)26=0(x+4)2=6x+4=±6x=4±6x^2 + 8x + 10 = 0 \rArr x^2+8x+16-16+10=0 \rArr (x + 4)^2 - 16 + 10 = 0 \rArr (x + 4)^2 - 6 = 0 \rArr (x+4)^2=6 \rArr x + 4 = \pm \sqrt{6} \rArr x = -4 \pm \sqrt{6} \rArr x=64x=\sqrt6-4 ose x=46x=-4-\sqrt6
  5. x26x+9=0(x3)2=0x3=0x=3x^2 - 6x + 9 = 0 \rArr (x - 3)^2 = 0 \rArr x - 3 = 0 \rArr x = 3
  6. x2+10x+24=0x2+10+2525+24=0(x+5)225+24=0(x+5)2=1x+5=±1x=5±1x=5+1=4=6x^2 + 10x + 24 = 0 \rArr x^2+10+25-25+24=0 \rArr (x + 5)^2 - 25 + 24 = 0 \rArr (x + 5)^2 = 1 \rArr x + 5 = \pm 1 \rArr x = -5 \pm 1 \rArr x=-5+1=-4 = -6 ose x=51=6x=-5-1=-6
  7. x2+22x+118=0x2+22x+121121+118=0(x+11)2121+118=0(x+11)2=3x+11=±3x=11±3x=311x^2 + 22x + 118 = 0 \rArr x^2+22x+121-121+118=0 \rArr (x + 11)^2 - 121 + 118 = 0 \rArr (x + 11)^2 = 3 \rArr x + 11 = \pm \sqrt{3} \rArr x = -11 \pm \sqrt{3} \rArr x=\sqrt3-11 ose x=113x=-11-\sqrt3
  8. x216x+54=0x216x+6464+54=0(x8)264+54=0(x8)210=0x8=±10x=8±10x=8+10x^2 - 16x + 54 = 0 \rArr x^2-16x+64-64+54=0 \rArr (x - 8)^2 - 64 + 54 = 0 \rArr (x - 8)^2 - 10 = 0 \rArr x - 8 = \pm \sqrt{10} \rArr x = 8 \pm \sqrt{10} \rArr x=8+\sqrt{10} ose x=810x=8-\sqrt{10}
  9. 4x212x+2=04x212x+99+2=0(2x3)29+2=0(2x3)27=02x3=±7x=3±724x^2 - 12x + 2 = 0 \rArr 4x^2-12x+9-9+2=0 \rArr (2x - 3)^2 - 9 + 2 = 0 \rArr (2x - 3)^2 - 7 = 0 \rArr 2x - 3 = \pm \sqrt{7} \rArr x = \dfrac{3 \pm \sqrt{7}}{2} \rArr x=3+72x=\dfrac{3+\sqrt7}{2} ose x=372x=\dfrac{3-\sqrt7}{2}
  10. 9x2+12x2=09x2+12x+442=0(3x+2)242=0(3x+2)26=03x+2=±6x=2±639x^2 + 12x - 2 = 0 \rArr 9x^2+12x+4-4-2=0 \rArr (3x + 2)^2 - 4 - 2 = 0 \rArr (3x + 2)^2 - 6 = 0 \rArr 3x +2 = \pm \sqrt{6} \rArr x = \dfrac{-2 \pm \sqrt{6}}{3} \rArr x=623x=\dfrac{\sqrt6-2}{3} ose x=263x=\dfrac{-2-\sqrt6}{3}
  11. x2+11x+3=0x2+11x+1122211222+3=0(x+112)21214+3=0(x+112)21094=0x+112=±1094x=11±1092x^2 + 11x + 3 = 0 \rArr x^2+11x+\dfrac{11^2}{2^2}-\dfrac{11^2}{2^2}+3=0 \rArr (x + \dfrac{11}{2})^2 - \dfrac{121}{4} + 3 = 0 \rArr (x + \dfrac{11}{2})^2 - \dfrac{109}{4} = 0 \rArr x + \dfrac{11}{2} = \pm \sqrt{\dfrac{109}{4}} \rArr x = \dfrac{-11 \pm \sqrt{109}}{2} \rArr x=109112x=\dfrac{\sqrt{109}-11}{2} ose x=111092x=\dfrac{-11-\sqrt{109}}{2}
  12. 9x230x32=09x230x+252532=0(3x5)22532=0(3x5)257=03x5=±57x=5±5739x^2 - 30x - 32 = 0 \rArr 9x^2-30x+25-25-32=0 \rArr (3x - 5)^2 - 25 - 32 = 0 \rArr (3x - 5)^2 - 57 = 0 \rArr 3x - 5 = \pm \sqrt{57} \rArr x = \dfrac{5 \pm \sqrt{57}}{3} \rArr x=5+573x=\dfrac{5+\sqrt{57}}{3} ose x=5573x=\dfrac{5-\sqrt{57}}{3}