Question

(х+1.4)^2-(х-1.4)^2+0.8х якщо х=1/4

Answer 1

$x {}^{2} + 2.8x + 1.4 {}^{2} - x {}^{2} + 2.8x - 1.4 {}^{2} + 0.8x = 6.4x = \frac{64}{10} \times \frac{1}{4} = \frac{16}{10} = 1.6$

Answer 2

(х+1.4)^2-(х-1.4)^2+0.8х=x^2+2,8x+1,96-x^2+2,8x-1,96+0,8x=5,6x+0,8x=6,4x=

=(64/10)*(1/4)=16/10=1,6