Question

what should be added in the polynomial X^2-5x+4 divisible by X-3.

Answer 1

When you divide $x^2-5x+4$ by $x-3$ the remainder is ($-2$)

So if you'll add negative of (-2) or say 2 to the equation $x^2-5x+4$ it gives $x^2-5x+6$ which is divisible by $x-3$

Just take an example:

What should be added to 2x - 1 to make it divisible by x

in this case clearly if -1 can be eliminated from the linear equation 2x - 1 then it will be divisible by x, so, to eliminate -1 we add 1 to the equation which gives us 2x, which is divisible by x.

Answer 2

Here is your answer in the attachment

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