Question:
A lighthouse L is located on a small island 4 km west of
Last updated: 10/16/2023
A lighthouse L is located on a small island 4 km west of point A on a straight north south coastline A power cable is to be laid from L to the nearest source power at point B on the shoreline 12 km north of point A The cost of laying c under water is 6000 km and the cost of laying cable along the shoreline is 2000 km To minimize the cost the power line will be built from L underwat point C on the shoreline and then along the shoreline from C to B Find the loc of point C to the nearest metre on the shoreline where the power cable shoul enter the water represents the distance the amount of cable laid underwater represents the distance the amount of cable is laid on shore