Final answer:
A polynomial expression with 7 different terms that simplifies to 3 terms is '3x^2 + 2x^2 + x^3 + 4x^3 - x^3 + 5 - 2', which after combining like terms and eliminating terms, simplifies to '5x^2 + 4x^3 + 3'.
Step-by-step explanation:
To create a polynomial expression with 7 different terms that can be simplified to exactly 3 terms, we can include terms with like variables and exponents that combine when simplified. For example:
3x^2 + 2x^2 + x^3 + 4x^3 - x^3 + 5 - 2 is a polynomial with seven terms.
When we eliminate terms and combine like terms, the expression simplifies to:
(3x^2 + 2x^2) + (x^3 + 4x^3 - x^3) + (5 - 2)
This simplifies further to:
5x^2 + 4x^3 + 3
Here, we have successfully combined terms, and after checking if the answer is reasonable, we are left with a simplified polynomial of exactly 3 terms.