Answer:
Step-by-step explanation: We have to add how much time it took him to do all of his homework. To do this, we have to add 2/3 and 3/5.
First, we have to find a LCM between 3 and 5.
The LCM between those numbers are 15.
Next we find out what number to multiply 3 by to get 15, we multiply it by 5.
2 * 5 = 10
3 * 5 = 15
Next we find out what number to multiply 5 by to get 15, we multiply it by 3.
3 * 3 = 9
5 * 3 = 15
10/15+9/15=19/15
We are left off with 1 4/15
So it took him 1 hour and 4/15 minutes to do his homework.
Step-by-step explanation:
use the formula: (a+b)³ = a³+3a²b+3ab²+b³
and place the corresponding values.
Answer:
810
Step-by-step explanation:
What is the context for the question if there is any?
Answer:
x²+1/x² = 51
Explanation:
Given x - 1/x = 7 ---(1)
We know the algebraic identity:
a²+b²-2ab = (a-b)²
Or
a²+b² = (a-b)²+2ab
Now,
x²+1/x²
= (x-1/x)²+2*x*(1/x)
= (x-1/x)²+2
:7²+2 [ from (1)] =
= 49+2
= 51
Therefore,
x²+1/x² = 51