a Expand the expression b Simplify the expression c Simplify
(a) Expand the expression: (b) Simplify the expression: (c) Simplify the expression: (x - 3)(2x + 7) = 2x^2 + x - 21 5 squareroot -32 = -2 a^2 - b^2/a^2 - 2ab + b^2 = a + b/a - b: a notequalto b
Solution
a) ( x- 3) ( 2x + 7 )
using foil method to expand the expression
2x^2 + 7x - 6x - 21
2x^2 + x - 21
b) 5th root ( -32 )
-32 can be written in its factors
-32 = -2^ 5
5th root means raised to power 1/5
hence, we can write
(-2^5 )^1/5
= -2
c) ( a^2 - b^2 ) / ( a^2 - 2ab + b^2 )
factoring top and bottom expressions
a^2 - b^2 = (a-b) (a+b)
a^2 - 2a + b^2 = (a-b)^2
now the expression becomes
( a-b) (a+b) / (a-b) (a-b)
= a+b / a-b
a should not be equal to b
