Proof -
So, in the first part we'll verify by taking n = 1.



Therefore, it is true for the first part.
In the second part we will assume that,

and we will prove that,








<u>Henceforth, by </u><u>using </u><u>the </u><u>principle </u><u>of </u><u> mathematical induction 1²+2² +3²+....+n² = n(n+1)(2n+1)/ 6 for all positive integers n</u>.
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Answer:

Step-by-step explanation:
When we multiply a polynomial by a specific monomial, all terms in the polynomial get multiplied by the monomial.
So we can do this by term.

Multiplying x by x to the something power will just increase the exponent on the x term by one (since powers are just x multiplied by itself). This means the exponent here will increase by 1, so this becomes
.
Same logic applies to the second term:
, raise the exponent by one,
.
For the third term, if there is no exponent on a term you can assume it's exponent is 1 (so
in this case - as
). Again, using the same logic, this turns into
.
For the last term, when we multiply a constant by a variable, we get a term with a variable and a coefficient - the constant becomes the coefficient and the variable stays the variable. Therefore,
.
Adding these terms all together gets us
.
Hope this helped!