How do you combine 1x3+1(x3)21(x3)3 into one term?

2 Answers
Dec 5, 2017

x25x+5x3+9x2+27x27=x25x+5(x3)3

Explanation:

1x3+1(x3)21(x3)3

Take (x3)=a, So,

(x3)2=x26x+9 ------------ =a2 and
(x3)3=x3273×x2(3)+3××x(9)

(x3)3=x3279×x2+27x

(x3)3=x3+9x2+27x27------a3

And, given expression can be written as:

1a+1a21a3

Now solve by equating the denominators:

1a+1a21a3

1a(a2a2)+1a2(aa)1a3

a2a3+aa31a3

a2+a1a3

Substitute values:

x26x+9+x31x3+9x2+27x27

x25x+5x3+9x2+27x27

x25x+5(x3)3

Dec 5, 2017

x25x+5(x3)3

Explanation:

we require the fractions to have a common denominator

the common denominator of

(x3),(x3)2 and (x3)3 is (x3)3

multiply numerator/denominator of

1x3 by (x3)2

1x3×(x3)2(x3)2=(x3)2(x3)3

multiply numerator/denominator of

1(x3)2 by (x3)

1(x3)2×x3x3=x3(x3)3

putting this together gives

(x3)2(x3)3+x3(x3)31(x3)3

the fractions have a common denominator so add
the numerators leaving the common denominator

=x26x+9+x31(x3)3

=x25x+5(x3)3(x3)