Given the function f (x) = 4-x + 1: X-1 under the root sign, the domain of definition of F (x) and the value of F (2) are obtained

Given the function f (x) = 4-x + 1: X-1 under the root sign, the domain of definition of F (x) and the value of F (2) are obtained

If 4-x > = 0 under the root sign, we get X

The definition field of [Log1 / 2 (X & # 178; - 1)] under the function y = root sign is (). For detailed explanation, explain: the whole formula is in the root sign

The mode of being opened is not negative
log(1/2) (x²-1)≥0
That is log (1 / 2) (X & # 178; - 1) ≥ log (1 / 2) 1
∴ 0

The domain of the function y + 1 / (1-2cosx) is

1-2cosx as denominator, cannot be equal to zero
So 1-2cosx is not equal to 0
Cosx is not equal to 1 / 2
So the domain of X: X is not equal to 2K π + π / 3 or 2K π - π / 3