Question

x2 + x - (a + 1)(a + 2) = 0 by factorisation

Answer 1

Answer:

x = - a - 2  or   a + 1

Step-by-step explanation:

⇒ x^2 + x - ( a + 1 )( a + 2 ) = 0

      Spitting the middle term in such a manner so that product of term with x^2 and constant become equal.

 Here, those parts are a + 2 and a + 1.

⇒ x^2 + x( 1 ) + ( a + 2 )( a + 1 ) = 0

⇒ x^2 + x[ a - a + 2 - 1 ] - ( a + 2 )( a + 1 ) = 0

⇒ x^2 + x[ ( a + 2 ) - ( a + 1 ) ] - ( a + 2 )( a + 1 ) = 0

⇒ x^2 + x( a + 2 ) - x( a + 1 ) - ( a + 2 )( a + 1 ) = 0

⇒ x[ x + a + 2 ] - ( a + 1 )[ x + a + 2 ] = 0

⇒ ( x + a + 2 )( x - a - 1 ) = 0

   Values of x are :

   x = - a - 2   or  a + 1