I need your help.
pleas I need some one to explain for me what does secant mean in mathematics?
Clear example with images would be appreciated.
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$\begingroup$In geometry, a secant is a line that intersects a circle twice.
In calculus, the secant line is a line that (locally) intersects a curve twice. It is used to approximate the slope within a particular interval.
In the image, the line that intersects twice is called the secant line, the line tangent to a point is the tangent line.
This is where the geometric definition of the derivative comes from.
The slope of the secant line (intersecting the curve at $(x,f(x))$ and at $(x+h,f(x+h)$) as $h\to0$ is the slope of the tangent line at the point $(x,f(x))$ (formula: $m=\lim_{h\to0}\frac{f(x+h)-f(x)}{h}$).
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