The method of finding function range Examples are given As long as the description of 1, inequality property method 2, discriminant method 3, substitution method 4, equation thought

The method of finding function range Examples are given As long as the description of 1, inequality property method 2, discriminant method 3, substitution method 4, equation thought

Function range: ① matching method: Transform to quadratic function, use the characteristics of quadratic function to evaluate; often transform to the form of; ② inverse method (inverse method): through the inverse solution, used to express, and then from the range of values, through the solution of inequality, get the range of values; commonly used to solve, such as: type; ④ ···················································

Some problems of finding function range
1. Inverse function method is used to find the range of function (3x + 4) / (5x + 6)
2. Find the range of function y = (e ^ x-1) / (e ^ x + 1)
3. Find the range of function y = (cosx) / (sinx-3)
4. The monotonicity method of function should be used
Find the range of function y = √ (x + 1) -√ (x-1)
5. Use the exchange method
Find the range of function y = x + √ (x-1), find the range of function y = (SiNx + 1) (cosx + 1), X ∈ [- π / 12, π / 2]
Find the range of function y = x + 4 + √ (5-x2)
I can write a few words

1 X=4/(5y-3) y≠3/5 y∈R
2 y = 1-1 / (e ^ x + 1) monotone increasing function y > - 1 and y = 0) y > = 1
(2) Let t = SiNx + cosx (T ^ 2-1) / 2 = SiNx × cosx y = (T ^ 2-1) / 2 + t

Find the range of function y = 3x + 1, where x is all real numbers

It's all real numbers