Loading [MathJax]/jax/output/SVG/jax.js
 
+0  
 
0
896
2
avatar+257 

The two imaginary solutions of (x-1)(x-2)(x-3)=(6-1)(6-2)(6-3) satisfy the equation x^2+k=0 What is the value of k? I got +-36 but this isn't imaginary so I don't know if this is correct.

 Mar 13, 2019
 #1
avatar+118703 
+4

No it is not correct.    sad

 

I think i did it the hard way,....

 

(x-1)(x-2)(x-3)=(6-1)(6-2)(6-3)   

So x=6 is one solution.  

It is a cubic so there is a total of 3 answers for x.   

The other 2 satisfy   x^2+k=0

 

Maybe there is a quicker way to do it but I expanded the left.

(x1)(x2)(x3)=543x36x2+11x6=60x36x2+11x66=0Then I divided the LHS by (x-6) and got(x6)(x2+11)=0Sox=6,andx2=11x2=11x=±11x=x=±11i

 

But you were not asked for all the x solutions you were asked for k and  k=11

 Mar 13, 2019
 #2
avatar+257 
+1

Thank you for explaining and letting me know I was wrong! smiley

SydSu22  Mar 14, 2019

1 Online Users