Hi @likhith ,
Are the 3 beeps actually 1 beep followed by 2 more? {being pedantic I know ;-)}
If so, this indicates a checksum failure.
This could be due to a depleted CMOS battery. (It could also be called a RTC battery ('''R'''eal '''T'''ime '''C'''lock) or a BIOS battery)
Here’s a link to a [https://www.youtube.com/watch?v=DYbaY3JxE2o|video] that shows how to replace the CMOS battery in an Acer Aspire 5740DG.
As I couldn’t find a video for your particular model, I hope it is a close enough model number to yours to be of some help. You may have better luck in finding a CMOS battery replacement video or guide for your laptop.