Question

1) (-0,4)^3 +(-0,2)^3=? 2) 5• (-2/5)^3=?3) (7^3 : 200 - 0,4^2) : (-0,5)^3=? 4) (2,6 - 2,2)^3 • (- 1 3/7)^2=?^ - ОБОЗНАЧЕНИЕ СТЕПЕНИ 1 3/7 - ОДНА ЦЕЛАЯ ТРИ СЕДЬМЫХ​

Answer 1

1) (-0,4)^3 + (-0,2)^3 =
= -0,064 - 0,008 = - 0,072

2) 5 • (-2/5)^3 =
= 5 • (-8/125) =
= -8/25 = -0,32

3) (7^3 : 200 - 0,4^2) : (-0,5)^3 =
= (7^3 : 200 - (2/5)^2) : (-1/2)^3 =
= (343/200 - 4/25) : (-1/8) =
= (343/200 - 32/200) : (-1/8) =
= 321/200 : (-1/8) =
= - 321/200 • 8 =
= -321•8/200 = -
= - 321 • 4 / 100 =
= - 1284/100 = -12,84

4) (2,6 - 2,2)^3 • (- 1 3/7)^2 =
= (0,4)^3 • (-10/7)^2 =
= (4/10)^3 • (-10/7)^2 =
= 64/1000 • (-100/49) =
= -640/49 = -13 3/49

Answer 2

Let's solve each of these expressions step by step:

1. $(-0.4)^3 + (-0.2)^3$

Calculating each term individually:

$(-0.4)^3 = -0.064$ $(-0.2)^3 = -0.008$

Adding them together:

$(-0.064) + (-0.008) = -0.072$

So, $(-0.4)^3 + (-0.2)^3 = -0.072$.

2. $5 \cdot \left(-\frac{2}{5}\right)^3$

$\left(-\frac{2}{5}\right)^3 = -\frac{8}{125}$

Multiplying by 5:

$5 \cdot \left(-\frac{8}{125}\right) = -\frac{40}{125} = -\frac{8}{25}$

So, $5 \cdot \left(-\frac{2}{5}\right)^3 = -\frac{8}{25}$.

3. $\frac{7^3}{200} - 0.4^2 \div (-0.5)^3$

Calculating each part:

$7^3 = 343$ $0.4^2 = 0.16$ $(-0.5)^3 = -0.125$

$\frac{7^3}{200} - 0.4^2 \div (-0.5)^3 = \frac{343}{200} - \frac{0.16}{-0.125}$

$\frac{343}{200} - \frac{0.16}{-0.125} = \frac{343}{200} + \frac{1.28}{0.125}$

$\frac{343}{200} + \frac{1.28}{0.125} \approx 1.715$

So, $\frac{7^3}{200} - 0.4^2 \div (-0.5)^3 \approx 1.715$.

4. $(2.6 - 2.2)^3 \cdot \left(-\frac{10}{7}\right)^2$

Calculating each part:

$2.6 - 2.2 = 0.4$ $-\frac{10}{7}$ as a decimal is approximately -1.428571...

$(0.4)^3 \cdot (-1.428571...)^2 \approx 0.064 \cdot 2.040816... \approx 0.130714...$

So, $(2.6 - 2.2)^3 \cdot \left(-\frac{10}{7}\right)^2 \approx 0.130714...$.

Please note that some of the results are approximated due to the use of decimal values and non-terminating decimals in the calculations.