Question

Regular expression (a+b)*a(a+b)* + b* represents

a)(a+b)*
b) (a+b)+
c) All words that have at least one a

Answer 1

The regular expression represents any string with 'a's and 'b's that contains at least one 'a'. The rule (xa)b = xa.b confirms the multiplication of exponents in the expression, affirming the correct answer as all words that have at least one 'a'.option c is correct.

Step-by-step explanation:

The given regular expression (a+b)*a(a+b)* + b* can be understood by examining its components.

• (a+b)* represents any number of 'a's and 'b's, including the empty string.
• a in the middle ensures that there is at least one 'a' in the string.
• (a+b)* after 'a' again represents any number of 'a's and 'b's, including the empty string.
• b* represents any number of 'b's, including the empty string.

Combining these parts, it is clear that the regular expression represents any string consisting of 'a's and 'b's that includes at least one 'a'. The correct answer is c) All words that have at least one a.