Answer:
The number is 53.
Step-by-step explanation:
If the digits are x and y where x is the first digit then we have the equations:
x + y = 8.........(1)
10x + y - (10y + x) = 18
9x - 9y = 18
Dividing through by 9:
x - y = 2..........(2)
Adding (1) and (2):
2x = 10
x = 5
and y = 8 - 5 = 3.
Common denominator would be 40, 3/4 becomes 30/40, 1/5 becomes 8/40, 5/8 becomes 25/40. 10 30/40 + 6 8/40 + 12 25/40 = 28 63/40 = 29 23/40
By the chain rule,
When
, we get
, so at this point the partial derivative of
with respect to
takes on a value of