Sin2(x) +cos(x)=1
from the relation: (sin2(x) +cos2(x) =1 )
so , sin2(x)=1-cos2(x)
by subs. in the main eqn.
1-cos2(x) + cos(x) =1
by simplify the eqn.
cos(x) -cos2(x)=0
take cos(x) as a common factor
cos(x)* (1-cos(x))=0
then cos(x)=0 && cos(x)=1
cos(x)=0 if x= pi/2
& cos(x) = 1 if x = 0 , 2*pi
so the solution is x= {0,pi/2 , 2*pi}
Four children average is 15.25 so ages must add to 61
61-12-16=33
11 and 22 go into 33
Youngest is 11
Okay so i would do this with a logarithm.
5^(2x) = 28
take the log of both sides
log5^(2x) = log28 and because of this log rule: logA^n = nlogA
(2x)log5= log28
then divide by log5 on both sides
2x = log28 / log5
and divide by 2
x = (log28 / log5) /2
this can be found with a calculator:
x= about 1.03521...
round that to whatever the question says to
Answer:
0.5 m/s
Falling at 32 feet/s
Step-by-step explanation:
For the first question, since it only asks for the average time between 2 and 8 seconds, those are the only two important values. When taking the inputs and outputs for 2 and 8 seconds after the throw ((2,3) and (8,6) respectively), we can take the average change by finding the change in y/change in x, so we have (6-3)/(8-2)=0.5 meters/second.
For the second question, we can similarly just take the values from the initial drop (144) and after two seconds (80) to get that the rate of change is (144-80)/(-2)=-32, so it's falling at 32 feet/second.
Let me know if you have any questions!
The mistake was when she multiplied the 2nd equation by 5, she forgot to also multiply that last number 10 by 5 as well.
correction :
5x + 3y - z = 15
-x + 2y + 3z = 10...multiply by 5
---------------------
5x + 3y - z = 15
-5x + 10y + 15z = 50 (result of multiplying by 5)
--------------------add
13y + 14z = 65
