geno3141

[(-6*3 + 4) - 5] + -2

Work from the inside out:

[(-18 + 4) - 5] + -2

[(-14) - 5] + -2

[-19] + -2

=  -21

Tan(π/2) is undefined; thus making the expression undefined.

However, if you are willing to play with the expression, you can do this:

tan(π/2)  =  sin(π/2) / cos(π/2)

1 - tan²(π/2)  =  sec²(π/2)  =  1 / cos²(π/2) 

So:  2·tan(π/2) / [1 - tan²(π/2) ]  =  [ 2·sin(π/2) / cos(π/2) ] / [ 1 / cos²(π/2) ]

=  [ 2·sin(π/2) / cos(π/2) ] · [ 1 / cos²(π/2) ]

= 2·sin(π/2)·cos(π/2)                               Since  sin(2x) = 2xin(x)cos(x):

= sin(2 · π/2)  =  sin(π)  =  0

For the problem   (0.5)^x  ≥  8

Let me show you two ways,

First way:  using logs:

Since the variable is an exponent, use logs:

     log(.05^x)  ≥  log(8)

The exponent comes out as a multiplier:

     x · log(0.5)  ≥  log(8)

Divide both sides by log(0.5); since log(0.5) is a negative number, reverse the direction of the inequality:

     x  ≤  log(8) / log(0.5)

     x  ≤  -3

Second way:  no logs:

(1/2)^x  ≥  8

2^(-x)  ≥  2^3

  -x  ≥  3

Dividing by -1 requires that we reverse the direction of the inequality:

   x  ≤  -3

35 is divisible by 1, 5, 7, and 35.

In the right triangle, if you are looking for ∠C, CB is the adjacent side while AC is the hypotenuse.

If you know the adjacent side and the hypotenuse, use the cosine.

cos = adj/hyp     ===>     cos(C)  =  22/60     ===>  cos(C)  =  0.366667

To find the size of the angle, use invcos:   C  =  invcos(0.366667)  =  68.5°

In that right triangle, the side BC is adjacent to ∠C and the hypotenuse is side AC.

If you know the adjacent and the hypotenuse, use the cosine:  cosine = adjacent / hypotenuse.

cos(C)  =  22 / 60     --->     cos(C)  =  0.36667

Find the invcos of both sides     --->   C  =  invcos(0.366667)  =  68.5°.

You have an underline in your problem; did you mean a minus sign?

88p - 80p + 2  =  -13                    Combine the 88p with the -80p:

          8p + 2  =  -13                    Subtract 2 from both sides:

                 8p  =  -15                   Divide both sides by 8:

                  p  =  =15/8

To divide by a fraction, multiply by the reciprocal. 

The reciprocal of  2/9  is  9/2.

-18 ÷ (2/9)  =  -18 x (9/2)  =  -162 / 2  =  -81

You are looking for the number of acres per pound of seed -- this means that you take the number of acres and divide that by the number of pounds of seed:

   8 acres / 61 pounds  =  0.13 acres/pound

I am assuming that you included n = 365 to mean that it is compounded 365 times a year.

The compound interest formula is:    A  =  P(1 + r/n)^(n·t)

A = Final Amount         P = Beginning Amount = 22,000         r = rate (as a decimal) = 0.03

n = number of times compounded per year = 365         t = number of years = 4

A  =  22000(1 + 0.03/365)^(365·4)    =    24,804.81