Precalculus Quiz 2024 Questions with Correct Answers

Precalculus Quiz 2024 Questions with Correct Answers What is the minimum force required to prevent a ball weighing 22.6 lb from rolling down a ramp which is inclined at 39.0 degrees with the horizontal? a. 7.1 lb c. 17.6 lb b. 8.8 lb d. 14.2 lb - Answer-X B Find a*b if a=10i+4j and b=3i+4j - Answer-C. 46 Find a*b if a=3i+8j and b=-0.5i-4j - Answer-B. -33.5 Determine whether the vectors u and v are orthogonal, parallel, or neither - Answer-A. neither The angle between a 180-pound force F and AB = 5i + 2j is 30 degrees. Find the work done by F in moving and object from A to B. - Answer-A. 839 foot lbs Use the dot product to find |v| when v=-2,-2 - Answer-X B A constant force of F = 47i + 30j moves an object along a vector D = 13i - 8j, where units are in pounds and feet. Find the work done. - Answer-B. 371 ft. lbs. Find the angle between u = (sqrt5)i-8j and v = (sqrt5)i+j Round to the nearest tenth of a degree. - Answer-B. 98.5 Find a*b if a=2,-8 and b=-1,4 - Answer-C. -34 Use the dot product to find |v| when v=-8,2 - Answer-X D X B Write the vector u as a sum of two orthogonal vectors, one of which is the vector projection of u onto v, projvu u= -8,-8 v= -1,2 - Answer-X B Use the dot product to find |v| when v=-2,-1 - Answer-X B Find the work done lifting a 290 lb weight 28 ft. in the air - Answer-X BF A piling for a high-rise building is pushed by two bulldozers at exactly the same time. One bulldozer exerts a force of 1250 pounds in a westerly direction. The other bulldozer pushes the piling with a force of 2650 pounds in a northerly direction. What is the magnitude of the resultant force upon the piling, to the nearest ten pounds? a. 2340 lbs. c. 3900 lbs. b. 2670 lbs. d. 2930 lbs. - Answer-D