How to prove $\sqrt[3]{7}$+$\sqrt{5}$ is irrational?

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We are learning the rational root theorem right now. It is pretty clear how to prove a number is irrational when we know how to construct a polynomial that only includes integer and has the irrational number as a root (rational root theorem). However, if it comes to sum of two number with different power, it is pretty hard to construct the polynomial. Is there a general way to construct polynomial? Or is there any alternative ways to prove this question?