... haveQ1P1R1Q1=Q1p1r1Q1,Q2P2R2Q2=Q2p2r2Q2,Q3P3R3Q3=Q3p3r3Q3, etc.,but the denominators of the fractions on the right hand of the equations areall of them, by hypothesis, unity. Therefore the steepness of the curve at the points P1, P2, ... ALPHABET OF ECONOMIC SCIENCE 26Now since the increase of the function is represented by the rising of the curve, the rate at which the function is increasing is the same thing as the rate at which the ... being the number of seconds since the projection, the height of the body in feet is always 128x − 16x2for allvalues of x, then we know by the rules, without further experiment,that the rate...