How to search Google, Yahoo!, Bing, and Wolfram|Alpha using Siri

Owning an iPhone and have been tired of typing to search for information? Then Siri can help you. Apple currently enables Siri to search Google (or Yahoo! or Bing) for general information, and Wolfram|Alpha for computational knowledge. Just ask, without typing needed, and you will get everything you need. Here is the detailed tutorial-How to use Siri search Google, Yahoo!, Bing, and Wolfram|Alpha.

How to search the web with Siri
Siri can search the web using whichever search engine you've set as default in Settings, under Safari. Unless you've changed it, that's Google. Other options are Yahoo! or Bing.
1. Press and hold down the Home button to activate Siri.

2. Tell Siri what you want to search for. For example, "Search for the best free iPad apps".

How to check alternate search engines with Siri
Don't want to change your default search engine, but still want to check a different search engine? Yes, Siri can do that too.
1. Press and hold down the Home button to activate Siri.
2. Tell Siri what you want to search for, and which search engine you want to use. For example, "Search Yahoo! for iMore" or "Search Bing for guitars".

How to query Wolfram|Alpha with Siri
Siri also has Wolfram|Alpha built right in. That is to say Siri can help you get answers to everything from basic equations to more advanced computations.
1. Press and hold down the Home button to activate Siri.
2. Tell Siri what you want to know. For example, "What is the square root of 8?" or "What is the value  of pi?"