Add.
(3x4 – 2x3 + 1) + (12x4 + x2 – 11)
answer
15x4 – 2x3 + x2 + 10
15x4 – x3 – 10
15x4 – x2 – 10
15x4 – 2x3 + x2 – 10

Here is how you are going to add the given polynomials:
3x^4     - 2x^3              -11
12x^4              +x^2     +1    <<< Add these using the normal addition process

15x^4 - 2x^3  +x^2 -10
Therefore, the answer would be the last option: 15x4 – 2x3 + x2 – 10
Hope this is the answer that you are looking for. Thanks for posting!

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