How do you solve #-3x^3 + 7x^2 = 4#?

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Answer 1 · 2015-09-16T18:54:17

The solutions are

#x_1=1,x_2=2,x_3=-2/3#

We set #p(x)=-3x^3+7x^2-4# and we notice that

#p(1)=0# hence #x-1# factor of the polynomial .Also

#p(2)=0# hence #(x-1)(x-2)# factor of the polynomial p(x).

It is easy to find now that #p(x)=(x-1)(x-2)(3x+2)#

Hence the solutions are

#x_1=1,x_2=2,x_3=-2/3#