Explicación paso a paso:
hola!
a)
[tex] {(2x - 5)}^{2} = [/tex]
usando diferencia de cuadrados :
[tex] {(2x)}^{2} - 2 \times 2x \times 5 + {5}^{2} [/tex]
[tex] {2}^{2} {x}^{2} - 2 \times 2x \times 5 + {5}^{2} [/tex]
[tex] {4x}^{2} - 2 \times 2x \times 5 + 25[/tex]
[tex] {4x}^{2} - 20x + 25[/tex]
B)
[tex](a ^{2} + \frac{1}{2} )^{2} [/tex]
usando cuadrado de suma :
[tex]( {a}^{2} )^{2} + {2a}^{2} \times \frac{1}{2} + ( \frac{1}{2} )^{2} [/tex]
[tex] {a}^{4} + {2a}^{2} \times \frac{1}{2} + \frac{1}{ {2}^{2} } [/tex]
[tex] = {a}^{4} + {a}^{2} + \frac{1}{4} [/tex]
espero te sirva saludos
