maths.free › Precalculus › Exponential and logarithmic functions
Exponential and logarithmic functions
Growth and decay, the number e, log rules, and change of base.
bˣ grows by the same factor for each unit of x; its inverse log_b x asks which exponent produces x. The rules log(ab) = log a + log b and log aᵏ = k log a are the exponent rules read backwards. Picture it: the exponential curve and its log are mirror images across y = x. Think it: e is the base whose growth rate equals its value, which is why calculus prefers it.
Ví dụ đã làm · y = e^x
Now you Chọn một bài toán, hoặc gõ hoặc vẽ của riêng mình. Mỗi bước, một bức tranh, câu trả lời ẩn cho đến khi bạn hỏi.
Ký hiệu được dùng ở đây
Nhấn vào bất kỳ ký hiệu nào để xem định nghĩa đầy đủ, một bức ảnh, và ý nghĩa của từng chữ cái trong nó.
Làm thế nào: Exponential and logarithmic functions
- An expression in x. Here is what it does.
- Derivative (slope).
Câu hỏi người ta hỏi
What is a function, really?
A rule that assigns exactly one output to each input. The vertical-line test on a graph is the same idea: no input may have two outputs.
Why do we need complex numbers?
Because x² + 1 = 0 has no real solution, and allowing one new number i with i² = −1 makes every polynomial equation solvable. They then turn out to describe rotation, waves and alternating current more naturally than real numbers do.
More in Precalculus
Complex numbersPolynomial functionsRational functionsSequences and seriesThe binomial theoremConic sectionsVectorsPolynomial division and the remainder theoremParametric equations and polar coordinates