Try to relax. Your desperation has surely progressed to the point where
you're unable to think clearly, and to agonize over it any further would only
cause you more pain and frustration.
I've never seen this kind of problem before. But I arrived here in a calm state,
having just finished my dinner and spent a few minutes rubbing my dogs, and
I believe I've been able to crack the case.
Consider this: (2)^a negative power = (1/2)^the same power but positive.
So:
Whatever power (2) must be raised to, in order to reach some number 'N',
the same number 'N' can be reached by raising (1/2) to the same power
but negative.
What I just said in that paragraph was: log₂ of(N) = <em>- </em>log(base 1/2) of (N) .
I think that's the big breakthrough here.
The rest is just turning the crank.
Now let's look at the problem:
log₂(x-1) + log(base 1/2) (x-2) = log₂(x)
Subtract log₂(x) from each side:
log₂(x-1) - log₂(x) + log(base 1/2) (x-2) = 0
Subtract log(base 1/2) (x-2) from each side:
log₂(x-1) - log₂(x) = - log(base 1/2) (x-2) Notice the negative on the right.
The left side is the same as log₂[ (x-1)/x ]
==> The right side is the same as +log₂(x-2)
Now you have: log₂[ (x-1)/x ] = +log₂(x-2)
And that ugly [ log to the base of 1/2 ] is gone.
Take the antilog of each side:
(x-1)/x = x-2
Multiply each side by 'x' : x - 1 = x² - 2x
Subtract (x-1) from each side:
x² - 2x - (x-1) = 0
x² - 3x + 1 = 0
Using the quadratic equation, the solutions to that are
x = 2.618
and
x = 0.382 .
I think you have to say that <em>x=2.618</em> is the solution to the original
log problem, and 0.382 has to be discarded, because there's an
(x-2) in the original problem, and (0.382 - 2) is negative, and
there's no such thing as the log of a negative number.
There,now. Doesn't that feel better.
Answer:
B. ) x² + 4x + 3
Step-by-step explanation:
(f-g)(x) = f(x) - g(x) =
(2x²-5) - (x²-4x-8) =
2x² - x² + 4x + 8 - 5 =
x² + 4x + 3
D = 10 is the diameter so r = d/2 = 10/2 = 5 is the radius
Plug r = 5 and h = 7 into the formula below and simplify
V = pi*r^2*h
V = pi*5^2*7
V = pi*25*7
V = pi*175
V = 175pi
Answer: Choice D
I’ll try to make a step by step demonstration! Feel free to skip to step 5 for the answer, though
1. The formula for a right triangular prism is (1/2)*base*height*length, and we know what the base (4 cm) and length (8 cm) are, but not the height
2. To find the height we must divide the side triangle into two, which then gives us two right triangles
3. Focusing on just one of the right triangles, its base will be 2 cm rather than 4 (as it has been divided by two) and its hypotenuse will be 4 cm; using Pythagorean’s theorem (a^2 + b^2 = c^2), solve for the missing side (the height), which should end up being √12
4. Multiply! (1/2)4*√12*8 ≈ 55.425
5. Round to the nearest tenth —> 55.4
I hope this helped somewhat! Comment if clarification is needed
