Question

f) (2x+5)²
g) (2x-5)²
h) (3x-1/2)²
i) (x+1/2)²
j) (x+1/x)²
Va rooog repede !
Dau coroana

Answer 1

f)
$(2{x})^{2} + 2 \times 2x \times 5 + {5}^{2} = 4 {x}^{2} + 20 + 25 = 4 {x}^{2} + 45$
g)
$(2 {x})^{2} - 2 \times 2x \times 5 - {5}^{2} = 4 {x}^{2} - 20 - 25 = 4 {x}^{2} - 5$
h)
$(3 {x})^{2} + 2 \times \frac{1}{2} \times 3 - (\frac{1}{2} )^{2} = 9 {x}^{2} + 6 \frac{1}{2} - { \frac{1}{2} }^{2} = 9 {x}^{2} + \frac{13}{2} - \frac{1}{4} = 9 {x}^{2} + \frac{26}{4} - \frac{1}{4} = 9 {x}^{2} + \frac{25}{4}$
i)
${x}^{2} + 2 \times \frac{1}{2} \times x + ( { \frac{1}{2} })^{2} = {x}^{2} + 2x \frac{1}{2} + \frac{1}{4} = {x}^{2} + \frac{5x}{2} + \frac{1}{4} = {x}^{2} + \frac{10x}{4} + \frac{1}{4} = {x}^{2} + \frac{11x}{4}$
j)
${x}^{2} + x \times 2 \times \frac{1}{x} + ({ \frac{1}{x} })^{2} = {x}^{2} + 2x \times \frac{2}{ {x}^{2} } = {x}^{2} + \frac{{2x}^{3} }{ {x}^{2} }$