For this problem,we use the Fundamental Counting Principle. You know that there are 7 digits in a number. In this principle, you have to multiply the possible numbers for every digit. If the first number cannot be zero, then there are 9 possible numbers. So, the value for the first digit is 9. The second digit could be any number but less of 1 because it was used in the 1st digit. So, that would be 10 - 1 = 9. The third digit must be the value in the second digit less than 1. That would be 9 - 1 = 8. And so on and so forth. The solution would be:
9×9×8×7×6×5×4 = 544,320 7-digit numbers
Answer is 4 :) I hope it help you.
Answer:
Step-by-step explanation:
The directional derivative of a function in a particular direction u is given as the dot product of the unit vector in the direction of u and the gradient of the function
g(x,y) = sin(π(x−5y)
∇g = [(∂/∂x)î + (∂/∂y)j + (∂/∂z)ķ] [sin(π(x−5y))
(∂/∂x) g = (∂/∂x) sin (πx−5πy) = π [cos(π(x−5y))]
(∂/∂y) g = (∂/∂y) sin (πx−5πy) = - 5π [cos (π(x−5y))]
∇g = π [cos(π(x−5y))] î - 5π [cos (π(x−5y))] j
∇g = π [cos (π(x−5y))] [î - 5j]
So, the question requires a direction vector and a point to fully evaluate this directional derivative now.
Answer:
sphere...
Step-by-step explanation:
because...
just like if we increase the no. of faces of composite figures ...
surface area is increased ...
so no. of faces is infinite in sphere...
logically sphere have the greatest surface area
