Ask your own question, for FREE!
Mathematics 10 Online
OpenStudy (rane):

help !

OpenStudy (cybershadow):

Yes?

OpenStudy (rane):

consider the both equation \[x ^{5} = 16x ^{3}\] dividing both sies by x3 gives \[\frac{ x^5 }{ x^3} = \frac{ 16x^3 }{ x^3 }\] i.e and hence however, as well as these two solutions of x = 4 and x = -4 there is another value for x that satisfies the original equation. what is this 3rd solution tot he original equation?

OpenStudy (cybershadow):

x = 0? :P

OpenStudy (rane):

i.e \[x^2 = 16 \] and hence \[x = \pm4\]

OpenStudy (rane):

instead of dividing each side of the original equation by x^3 to solve it, instead subtract \[16x^3\] from each side and then factories and solve

OpenStudy (cybershadow):

see if u just put x = 0 , that wud satisfy the original equation , wont it ? :S

OpenStudy (cybershadow):

whatcha think?

OpenStudy (cybershadow):

so three solutions wud be x = 4,-4 and 0

OpenStudy (cybershadow):

@RANE

OpenStudy (anonymous):

if a queston is in that format don't do that by that approach, that can give you extraneous roots..... use this approach x^5-16x^3=0 then find the roots

OpenStudy (cybershadow):

i was just wondering if we can put x =0 that will satisfy the original equation i.e. 0^5 = 16 0^2 0 = 0 satisfied dont u think so? @divu.mkr

OpenStudy (anonymous):

but we are dividing x^2 both sides and if we put x=0 that will become invalid..and solution for every root is same

OpenStudy (nincompoop):

x^5 = 16x^3 x^5 - 16x^3 = 0

OpenStudy (nincompoop):

then factor

OpenStudy (rane):

thank you all of you

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!