In the previous section we saw limits that were infinity and itâs now time to take a look at limits at infinity. By limits at infinity we mean one of the following two limits. In other words, we are going to be looking at what happens to a function if we let x get very large in either the positive or negative sense.
Testing the Device. Bellâs assistant, Thomas Watson, was in a nearby room in Bellâs workshop, waiting to see if Bellâs device would work. Bell spoke these famous words into his device: âMr. Watson, come here. Watson heard the words clearly and distinctly, and thus, the first working model of a telephone was born. Although there were other inventors working on similar designs, including one whose patent application was almost on the same day as Bell submitted his, Bellâs invention was the first actual working telephonic device.
The First Mobile Phone. In 1946, Swedish police used the first mobile phone. The device was similar to a two-way radio but worked via a connection to the telephone network and the car's battery. The phone was able to make just six phone calls before draining the car battery.ts battery allowed for one hour of talk time and could store 30 numbers. These first-generation phones came in a tote back that could charge the battery via your car's cigarette light adapter. Others looked vaguely like briefcases that packed along larger batteries for longer talk time.