m_{tangent}$. What is a horizontal tangent line? A horizontal tangent line has a slope of zero ($m=0$). This occurs at local maximums and minimums of the function, where the derivative $f'(x)$ is equal to zero. Tangent Line Formulas Slope $$m = f'(x_0)$$ Point-Slope Form $$y - y_0 = m(x - x_0)$$ Normal Line Slope $$m_{\text{normal}} = -\frac{1}{m}$$ Related Calculus Tools Derivative Calculator Normal Line Calculator Secant Line Calculator Limit Calculator Integral Calculator

Calculators in m_{tangent}$. What is a horizontal tangent line? A horizontal tangent line has a slope of zero ($m=0$). This occurs at local maximums and minimums of the function, where the derivative $f'(x)$ is equal to zero. Tangent Line Formulas Slope $$m = f'(x_0)$$ Point-Slope Form $$y - y_0 = m(x - x_0)$$ Normal Line Slope $$m_{\text{normal}} = -\frac{1}{m}$$ Related Calculus Tools Derivative Calculator Normal Line Calculator Secant Line Calculator Limit Calculator Integral Calculator.