Note that the r you calculated is negative. How would we determine if this negative correlation is significant? Let's use a hypothetical example to illustrate. Suppose you caleulate r for 18 pairs of observations and find r-0.56. The DF = 16, and the critical value in the table would be 0.468. To test the significance of this negative r, you would ignore the negative sign, and see if it exceeds the critical value. You can think of the sign as indicating a direction, much like in velocity in physics. In our hypothetical example, the value 0.56 exceeds the critical value (0.468), so the correlation would be significant. Just be sure to report it as a significant negative correlation (-0.56). Is your negative correlation significant?

Use the ratio test to determnine whether an converges, where a, is given in the following problems. State if the %3D ratio test is inconclusive.

Multiply. (4.x – 1)(3x – 2) - O 11x – 12 O 12.x – 11 O 12.x2 + 11x – 2 O 12.r? – 11x +2 O 11x² – 12x +1

-11/16 + 3/4