Question

m^5+1.5m^4=15.04m^3 how to solve this question? 

i know just the answer are m=0,-4.7,3.2, but i dont know the solution !

pls help me !!

Answer 1

m^5+1.5m^4-15.04m^3=0; m^3(m^2+1.5m-15.04)=0. So m=0 is a solution.

m^2+1.5m-15.04=0 presents a solution (up to 2). This factorises: (m+4.7)(m-3.2)=0 because m^2-3.2m+4.7m-15.04=0 is the expansion and (4.7-3.2)m=1.5m, the middle term (4.7*3.2=15.04).

So m+4.7=0 or m-3.2=0 making the solutions m=-4.7 and 3.2 as well as m=0.