Answer:
a) (8,8,-6)
b) 4x+4y+3z = -3
Step-by-step explanation:
a)
The surface is given by the equation
f(x,y,z) = 0 where
The gradient of this function is the vector
If we evaluate it in the point P = (-2,2,1) we obtain the point
(8,8,-6)
b)
The vectors with their tails at P are of the form
(-2,2,1)-(x,y,z) = (-2-x, 2-y, 1-z)
as they must be orthogonal to the gradient, they must be orthogonal to the vector (8,8,6) so their inner product is 0
and the equation of the desired plane is
4x+4y+3z = -3
6 x 5 x 7 = 210
The volume formula is length x width x height :)
You divid the two numbers on top to equal the bottom and the factor one out
One
RemarkThis is very complicate unless you pick the right method. It's very handy o know about substitutions.
MethodLet z = (k + 2)^2
Now the problem becomes
z + 16/z = 92 Multiply through by z
Solutionz^2 + 16 = 92z
That does not look very promising. If you know the quadratic formula, this mess can be solved. If you do not know what the quadratic formula is, then what I've written is the answer.
Worse yet, you have to know what complex numbers are. Is this something you know about? The z form of this equation is fine. It gives answers that are rational. The problem is that both are negative and so in your next step, you will be forced to take the square root of a negative number.
Maybe the answer is just
(x + 3)^ + 16 = 92(x + 3)^2
If all you have to do is expand this then you get
x^2 + 6x + 9 + 16 = 92(x^2 + 6x + 9) Remove the brackets.
x^2 + 6x + 25 = 92x^2 + 552x + 828 Put the left over to the right.
0 = 92x^2 - x^2 + 552x - 6x + 828 - 25
0 = 91x^1 + 546x + 803
It looks that way from the second question. If I'm wrong about that, put a comment down below.
Two Put over a common denominator and expand
20 x 3/4 =
20/1 x 3/4= turn the 20 into a fraction
20 x 3 / 1 x 4
60/4 =
15
The answer is 15. :)
