The product of two equal values can be expressed by one of these squared values. For example,
[tex]\mathsf{(2x+3)(2x+3)=(2x+3)^2}[/tex]
The sum of two terms squared can be solved by a remarkable product called "square of the sum of two terms", which is expressed as follows:
- [tex]\mathsf{(a+b)^2=a^2+2ab+b^2}[/tex]
Developing, changing the values, we will have:
[tex]\begin{array}{rl} \mathsf{(2x+3)^2}&\mathsf{=(2x)^2+2(2x)(3)+3^2}\\\\ &\mathsf{=4x^2+4x(3)+9}\\\\ \underline{&\mathsf{=4x^2+12x+9}} \end{array}[/tex]
The answer is C.
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The development of remarkable products is done as follows:
[tex]\begin{array}{rl} \mathsf{(a+b)^2}&\mathsf{=(a+b)\cdot(a+b)}\\\\ &\mathsf{=a^2+ab+ab+b^2}\\\\ &\mathsf{=a^2+2ab+b^2}\end{array}[/tex]
