Menu Close

2-2x-1-1-3-x-3-1-How-much-the-x-is-




Question Number 167508 by Bagus1003 last updated on 18/Mar/22
2((2x+1))^(1/3) =x^3 −1  How much the x is?
22x+13=x31Howmuchthexis?
Answered by alephzero last updated on 18/Mar/22
2((2x+1))^(1/3)  = x^3 −1  ⇒ ((2x+1))^(1/3)  = ((x^3 −1)/2)  ⇒ 2x+1 = ((x^9 −3x^6 +3x^3 −1)/8)  ⇒ 2x = ((x^9 −3x^6 +3x^3 −2)/8)  ⇒ x = ((x^9 −3x^6 +3x^3 −2)/(16))  ⇒ ((x^9 −3x^6 +3x^3 −8x−2)/(16)) = 0  ⇒ x^9 −3x^6 +3x^3 −8x−2 = 0  x_1  ≈ −0.9592  x_2  ≈ −0.2564  x_3  ≈ 1.4962
22x+13=x312x+13=x3122x+1=x93x6+3x3182x=x93x6+3x328x=x93x6+3x3216x93x6+3x38x216=0x93x6+3x38x2=0x10.9592x20.2564x31.4962
Answered by Jamshidbek last updated on 18/Mar/22
Solution.  2x+1=t ⇒ 2x=t−1  2((2x+1))^(1/3) =x^3 −1 ⇒ 16((2x+1))^(1/3) =(2x)^3 −8 ⇒  16t=(t−1)^3 −8 ⇒ t^3 −3t^2 +3t−1−8=16t  t^3 −3t^2 −13t−9=0  t^3 +t^2 −4t^2 −4t−9t−9=0  t^2 (t+1)−4t(t+1)−9(t+1)=0  (t+1)(t^2 −4t−9)=0  t_1 =−1  t_(2,3) =((4±(√(52)))/2)=2±(√(13))  x_1 =−1  x_(2,3) =((2±(√(13))−1)/2)=((1±(√(13)))/2)  Telegram:@math_undergraduate
Solution.2x+1=t2x=t122x+13=x31162x+13=(2x)3816t=(t1)38t33t2+3t18=16tt33t213t9=0t3+t24t24t9t9=0t2(t+1)4t(t+1)9(t+1)=0(t+1)(t24t9)=0t1=1t2,3=4±522=2±13x1=1x2,3=2±1312=1±132Telegram:@math_undergraduate
Commented by mr W last updated on 18/Mar/22
x_1 =−1  x_(2,3) =((1±(√5))/2)
x1=1x2,3=1±52

Leave a Reply

Your email address will not be published. Required fields are marked *