How do you multiply #(4z + \frac { 1} { 2} ) ^ { 2}# using the rule for the square of a binomial?

2 Answers
Apr 5, 2017

#16z^2+4z+1/4#

Explanation:

Recall,

#a^2=a*a#

So,

#(4z+1/2)^2=(4z+1/2)*(4z+1/2)#

Binomial expansion,

#16z^2+2z+2z+1/4#

Collect like terms,

#16z^2+4z+1/4#

Factor (if needed),

#4(4z^2+z+1/16)#

Apr 5, 2017

#16z^2 +4z+1/4#

Explanation:

The rule for squaring a binomial is a 5-step process:

  1. square the first term
  2. multiply the signs
  3. multiply the two terms and double
  4. PLUS
  5. square the last term

#(x+-y)^2 = x^2 +-2xy +y^2#

#(4z+1/2)^2 = 16z^2 +4z+1/4#

Applying the 5 steps:

  1. #(4z)^2 = 16z^2#
  2. #+ xx + = +#
  3. #4z xx 1/2 xx2 = 2z xx 2 = 4z#
  4. #+#
  5. #(1/2)^2 = 1/4#