Answer:
0 and arctan(0.5)
Step-by-step explanation:
if sin2x=2sinx*cosx and 1=sin²x+cos²x, then
cos²x+2sinxcosx-sin²x-cos²x=0;
2sinxcosx-sin²x=0; (to divide by cos²x)
2tanx-tan²x=0;
Answer:
Step-by-step explanation:
Without using the Routh-Hurwitz criterion at all, you know there is one positive real root. Descartes' rule of signs tells you the number of positive real roots is equal to the number of sign changes in the coefficients (perhaps less a multiple of 2). There is one sign change in + + + + - - , so there is one positive real root.
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(a) The Routh array starts as two rows of the polynomial's coefficients, alternate coefficients on each row. For this odd-degree polynomial, the number of coefficients is even, so no zero-padding is necessary at the right end of the second row. That is, we start with ...
The next row is formed from combinations of coefficients in the two rows above. The computation is similar to that of a determinant. By matching the numbers to those in the array, you can see the pattern of the computation.
The next row values are ...
Simplifying, we find this row to be ...
The zero row is a special case that requires we proceed as follows. The row above (identified with s⁴) represents an "auxiliary polynomial":
To continue the process, we replace the zero row by the coefficients of the derivative of this auxiliary polynomial. Proceeding as before, the array now becomes ...
The number of sign changes in the first column (1) tells the number of roots in the right half-plane. The auxiliary polynomial will give us the remaining two pairs of roots:
So, we have determined there to be ...
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(b) The original polynomial can be factored as ...
p(s) = (s +2)(s² +25)(s +1)(s -1)
p(s) = (s +2)(s +1)(s -5i)(s +5i)(s -1)
This verifies our result from part (a).
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Additional comments
Any row can be multiplied by a convenient factor to simplify the arithmetic. Here, it would be convenient to divide the second row by 2 and the third row by 8.
A zero element (not row) in the first column is replaced by "epsilon" (a small positive number) and the rest of the arithmetic is continued as normal. That row is not counted (it is ignored) when counting sign changes in the first column.
−200 ÷ −25
A) The quotient of two even integers is always positive.
B) The product of two even integers is always positive.
C) The quotient of two negative integers is always negative.
D) The quotient of two negative integers is always positive.
The equation to solve this problem is 114 + 2.75x = 320.25. Solving this equation, we find that the cost of labor per hour, represented by x, is $75.
The problem you're trying to solve involves the labor cost per hour of the technician who worked on Caroline's computer. From the problem, we know that the total cost of the repair was $320.25. This includes the cost of parts, which was $114, and the labor the technician invested, which we know took 2.75 hours but we aren't sure of the per hour cost. Let's denote this unknown cost as x. Therefore, our equation would be 114 + 2.75x = 320.25.
We can solve for x, the cost of labor per hour, by isolating this variable on one side of the equation. Firstly, subtract 114 from both sides: 2.75x = 320.25 - 114 which results in 2.75x = 206.25. Then, divide both sides by 2.75 to find x: x = 206.25/2.75 which equals $75. Therefore, the cost of labor per hour is $75.
#SPJ3
Answer: A
Step-by-step explanation:
You want to make them both have common denominators. What number does the denominators both go into? Thats easy, its 60.
Multiply 7/12 by 5/5 to get 35/60
Now multiply 4/15 by 4/4 to get 16/60
You need to add a negative number to 35/60 in order to get 16/60
Do 16-35 to get -19/60
supermarket 9 toilet rolls for £3.15 4 toilet rolls for £1.36
Work out which pack offers the best value for money.
Answer:
for the nine toilet pack, a toilet roll is 3.15/9 which is£0.35 while for the 4 toilet roll pack, a toilet roll is 1.36/4 which is £0.34 so the nine toilet pack gives the best value for money because a toilet roll sells for £0.35 which is £ 0.01 more than the four toilet pack