Question

calculati valoarea expresiei 0,8 x | a + 5 | - 1/2 x | 7/3 - b | + 8/15 pentru a = -6 si b = 5/3

Answer 1

0,8* |-6+5| -(1/2) * |7/3 - 5/3| + 8/15 =
= 0,8*|-1| - 1/2 * |2/3| + 8/15 =
= 8/10 * 1 - 1/2 * 2/3 + 8/15 =
= 4/5 - 1/3 + 8/15 =
= (12-5+8)/15 =
= 15/15 =
= 1

Answer 2

$0,8 \times | - 6 + 5| - ( \frac{1}{2}) \times | \frac{7}{3} - \frac{5}{3} | + \frac{8}{15} = \\ \\ - 6 + 5 = - 1 \\ \\ | - 1| = 1 \\ \\ 0,8 = \frac{8}{10} = \frac{4}{5} \\ \\ 0,8 \times 1 = \frac{4 \times 1}{5 \times 1} = \frac{4}{5} \\ \\ \frac{7}{3} - \frac{5}{3} = \frac{7 - 5}{3} = \frac{2}{3} \\ \\ | \frac{2}{3} | = \frac{2}{3} \\ \\ \frac{1}{2} \times \frac{2}{3} = \frac{1 \times2 }{2 \times 3} = \frac{2}{6} = \frac{1}{3} \\ \\ \frac{4}{5} - \frac{1}{3} = \frac{4 \times 3}{5 \times 3} - \frac{1 \times 5}{3 \times 5} = \frac{12}{5} - \frac{5}{15} = \frac{12 - 5}{15} = \frac{7}{15} \\ \\ \frac{7}{15} + \frac{8}{15} = \frac{7 + 8}{15} = \frac{15}{15} = 1$