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Solve x+148x2+x+2310x2=3

 Jul 31, 2020
 #1
avatar+33657 
+2

As follows:

 

 Jul 31, 2020
 #2
avatar+26396 
+2

Solve x+148x2+x+2310x2=3

 

Substitute: y=x2ory2=x2x=y2+2

 

x+148x2+x+2310x2=3y2+2+148y+y2+2+2310y=3y28y+16+y210y+25=3y28y+16=(y4)2=(4y)2y210y+25=(y5)2=(5y)2

 

Case 1:y28y+16=(y4)2y210y+25=(y5)2(y4)2+(y5)2=3y4+y5=32y9=32y=9+32y=12y=6Case 2:y28y+16=(y4)2y210y+25=(5y)2(y4)2+(5y)2=3y4+5y=313no solution!Case 3:y28y+16=(4y)2y210y+25=(5y)2(4y)2+(5y)2=34y+5y=32y+9=32y=932y=6y=3Case 4:y28y+16=(4y)2y210y+25=(y5)2(4y)2+(y5)2=34y+y5=313no solution!


First solution:y=6x=y2+2x=62+2x=38Second solution:y=3x=y2+2x=32+2x=11

 

laugh

 Jul 31, 2020
edited by heureka  Jul 31, 2020

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