Logarithmic functions have a characteristic shape when graphed. Here are some key features to look for in a logarithmic graph:
1. Asymptote: Logarithmic graphs have a vertical asymptote at x = 0. This means that the graph approaches but never touches the y-axis.
2. Shape: The shape of a logarithmic graph is curved, resembling a slow but steady increase or decrease. The curve can be concave up or concave down, depending on the base of the logarithm.
3. Domain and range: The domain of a logarithmic function is all positive real numbers, while the range is all real numbers. This means that the graph extends indefinitely in both directions.
4. Intercepts: A logarithmic function will have a y-intercept at (0, a) where a is a constant value. There will be no x-intercepts because the graph never crosses the y-axis.
5. Slant asymptote: If there is a horizontal shift in the logarithmic function, there may be a slant asymptote. This occurs when the curve approaches but never touches a diagonal line.
By observing these characteristics, you can easily identify a logarithmic graph.