Page 62 - Standard Handbook Of Petroleum & Natural Gas Engineering

Analytic Geometry 51

V
V

I
X

Figure 1-36. Asymptote of a curve. Figure 1-37. Slope of a straight line.

Equations of Slope

1. Two-point equation (Figure 1-37)

--
Y -Y1 = Y'L-Y1
x-XI X2-X1
2. Point slope equation (Figure 1-37)

y - YI = m(x - XI)
3. Slope intercept equation (Figure 1-37)
y=mx+b

Tangents

If the slope m of the curve of f(x) at (xI,yI) is given by (Figure 1-38)

V norm

Figure 1-38. Tangent and normal to a curve.