Hello there, Thanks for using Justanswer. I am Nimman and I will be assisting you.
The main difference is Multicore CPU executes multiple instructions at the same time.
A Quad core having 4 cores compared to the Dual core ( Which have only 2 ) cores can executes 2 times more instructions .
So, a quad core chip may be able to execute the instructions four times faster, but that doesn’t mean it can receive instructions from ram four times faster.
Most of the new softwares are written to take full advantage of multi-core processors. The operating system might provide a small automatic increase in speed, but you won’t see a 4X increase in performance simply by switching to a quad core. But there will be a difference .
And a quad core will be better in Multitasking also.
Please let me know if you have any doubts.