Find the cube of( -5 1
7
) .
Answers
Answered by
0
Answer:
:
According to the identity:
{(x - y)}^{3} = {x}^{3} - {y}^{3} - 3 {x}^{2} y + 3x {y}^{2}(x−y)
3
=x
3
−y
3
−3x
2
y+3xy
2
Taking:
5 = x
And
1/7 = y
\begin{gathered} {(5 - \frac{1}{7}) }^{3} = {5}^{3} - { \frac{1}{7} }^{3} - 3 \times {5}^{2} \times \frac{1}{7} + 3 \times 5 \times { (\frac{1}{7} })^{2} \\ \\ = 》 125 - \frac{1}{343} - \frac{75}{7} + \frac{15}{49} \\ \\ = 》 \frac{42875 - 1 - 3675 + 105}{343} \\ \\ = 》 \frac{39304}{343} \end{gathered}
(5−
7
1
)
3
=5
3
−
7
1
3
−3×5
2
×
7
1
+3×5×(
7
1
)
2
=》125−
343
1
−
7
75
+
49
15
=》
343
42875−1−3675+105
=》
343
39304
Answered by
2
Answer:
the cube of -517 is 8.0259573526
hope it helps you mate keep smiling good evening
Similar questions