geno3141

(52 - 3x² -4y²)^1/2

First derivative --->   (1/2)(52 - 3x² - 4y²)^-1/2(-6x - 8yy')

Use the formula:  A = Pe^rt

where A = final amount

          P = initial amount (amount invested)

          e = base of natural logarithms

          r = rate (as a decimal)

          t = time (number of years if r is a yearly rate). 

To answer this question, let's first try an easier question:

How any integers are greater than 3 but less than 10?

The answer is 6 and they are 4, 5, 6, 7, 8, and 9.

Yet, when we subtract 3 from 10, we get 7:  10 - 3 = 7. This is 1 more than the answer.

So, the number of integers greater than 87 and less than 321, we should subtract 87 from 321, and then subtract 1 from that answer:  (321 - 87) - 1  =  233!

The two digit positive numbers divisible by 5 are:  15, 25, 30, ..., 90, 95

(there are 17 of them).

Of them, those that are divisible by 3 are 15, 30, 45, 60, 75, and 90

(there are 6 of them).

That means, that there are 11 remaining ...

If this is a direct proportion, set up:

--->   y₂ / x₂  =  y₁ / x₁

--->   y₂ / 5  =  48 / 2

Cross multiply:

--->   2·y₂  =  5 · 48

--->   2·y₂  =  240

Divide both sides by 2:

--->   y₂  =  120

u - 9  =  7u + 7

Subtract u from both sides:

    -9  =  6u + 7

Subtract 7 from both sides:

   -16  =  6u

Divide both sides by 6:

   -16/6  =  u

--->  u  =  -8/3

You'll need to be more specific; does the 0.98 represent one standard deviation?

2xi(i - 4i²)  =  (2xi)(i) - (2xi)(1²)  =  2xi² - 2xi³

If i = √(-1), then i² = -1 and i³ = -i:

   --->   2xi² - 2xi³  =  2x(-1) - 2x(-i)  =  -2x + 2xi

Since 1° = 60', change one of the 90° into minutes to give  89° 60'.

The problem now is:  89° 60'  -  1° 42'  =  88° 18'.