The simplified expression e2t + 2 + e−2t inside the radical can be re-written as

The term e is not a variable but an irrational number called the Euler's number. The given equation is written as: e^(2t) + 2 + e^(-2t). From the law of exponents, you can combine the constants with the same base. SO,

e^(2t - 2t) + 2 = e^0 + 2

It is also in the law of exponents that any value raised to the power of zero is 1. Therefore, the simplified equation would be 2.