Answer:
c=80
Step-by-step explanation:
Based on my reading the critical damping occurs when the discriminant of the quadratic characteristic equation is 0.
So let's see that characteristic equation:
20r^2+cr+80=0
The discriminant can be found by calculating b^2-4aC of ar^2+br+C=0.
a=20
b=c
C=80
c^2-4(20)(80)
We want this to be 0.
c^2-4(20)(80)=0
Simplify:
c^2-6400=0
Add 6400 on both sides:
c^2=6400
Take square root of both sides:
c=80 or c=-80
Based on further reading damping equations in form
ay′′+by′+Cy=0
should have positive coefficients with b also having the possibility of being zero.
Alright, lets say the measure of the 3rd angle (the smallest one) is x degree, then measure of the 1st angle will be (x + 25) degree, and 2nd one: 3x degree. The sum of all the angles in any triangles is 180 degrees.
(x + 25) + 3x + x = 180
5x + 25 = 180 ---> 5x = 180 - 25 ---> 5x = 155 ---> x = 155/5 ---> x = 31o (third angle)
31 + 25 = 56o (first angle)
3 × 31 = 93o (second angle)
56 + 93 + 31 = 180
Answer: 32.14 after round off it will be 32
Step-by-step explanation:
This is how to round 32.14 to the nearest whole number. In other words, this is how to round 32.14 to the nearest integer.
32.14 has two parts. The integer part to the left of the decimal point and the fractional part to the right of the decimal point:
Integer Part: 32
Fractional Part: 14
Our goal is to round it so we only have an integer part using the following rules:
If the first digit in the fractional part of 32.14 is less than 5 then we simply remove the fractional part to get the answer.
If the first digit in the fractional part of 32.14 is 5 or above, then we add 1 to the integer part and remove the fractional part to get the answer.
The first digit in the fractional part is 1 and 1 is less than 5. Therefore, we simply remove the fractional part to get 32.14 rounded to the nearest whole number as:
32
Since sin(2x)=2sinxcosx, we can plug that in to get sin(4x)=2sin(2x)cos(2x)=2*2sinxcosxcos(2x)=4sinxcosxcos(2x). Since cos(2x) = cos^2x-sin^2x, we plug that in. In addition, cos4x=cos^2(2x)-sin^2(2x). Next, since cos^2x=(1+cos(2x))/2 and sin^2x= (1-cos(2x))/2, we plug those in to end up with 4sinxcosxcos(2x)-((1+cos(2x))/2-(1-cos(2x))/2)
=4sinxcosxcos(2x)-(2cos(2x)/2)=4sinxcosxcos(2x)-cos(2x)
=cos(2x)*(4sinxcosx-1). Since sinxcosx=sin(2x), we plug that back in to end up with cos(2x)*(4sin(2x)-1)
