Let the remainder

Equation
From equation

Hence remainder

If  is a factor then

Equation (2) - (1) we have
From equation (2)

3. 
   Whout doing long division, we can rearrange this polynomials and get the required proof.

Here we see that  is a factor or the Syromial.
Factorising completely we have

If you cannot see the factors easily, do your long division of polynomials.

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Here we carry out long division first

Therefore

We now express  in partial fractions thus
At this level dear student; I am convinced you can solve or the constants  and .
Solve and see whether your result is

Here we carry out long division first

Therefore

We now express  in partial fractions thus
At this level dear student; I am convinced you can solve or the constants  and .
Solve and see whether your result is

We may also proceed as follows

Now complete the solution and check your result with

We may also proceed as follows

Now complete the solution and check your result with