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avatar+1348 

Find all values of a that satisfy the equation
a3+1=a+3aa2+2a.

 Jan 13, 2024
 #1
avatar+291 
+1

Let's simplify:

 

a3+1=1+3aa+2a

 

a5a+a3=0

 

I just put this on a calculator and got a = 152152

 

I didn't know what to do.

 

Answer: (sqrt 15)/2, -(sqrt 15)/2

 Jan 13, 2024
 #2
avatar+130466 
+1

Simplify as

 

(a + 3) / 3 =    [ -a^2 + a + 1 ] /  a             cross-multiply

 

a ( a + 3)  =  3 (-a^2 + a + 1)

 

a^2 + 3a   = -3a^2 + 3a + 3

 

4a^2  = 3

 

a^2  = 3/4                 take both roots

 

a = sqrt (3)  / 2          or     a =   -sqrt (3)  / 2

 

cool cool cool

 Jan 13, 2024

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