So you can do this multiple ways, I'll do this the way that I think makes sense the l most easily.
Cos (0) = 1
Cos (pi/2)=0
Cos (pi) =-1
Cos (3pi/2)=0
Cos (2pi)=1
Now if you multiply the inside by 4, the graph oscillates more violently (goes up and down more in a shorter period).
But you can always reduce it.
Cos (0)= 1
Cos (4pi/2) = cos (2pi)=1
Cos (4pi) =Cos (2pi) =1 (Any multiple of 2pi ==1)
etc...
the pattern is that every half pi increase is now a full period as apposed to just a quarter of one. That's in theory.
Now that you know that, the identities of Cosine are another beast, but mathematically.
You have.
Cos (2×2t) = Cos^2 (2t)-Sin^2 (2t)
Sin^2 (t)=-Cos^2 (t)+1..... (all A^2+B^2=C^2)
Cos (2×2t) = Cos^2 (t)-(-Cos^2 (t)+1)
Cos (2×2t)= 2Cos^2 (2t) - 1
2Cos^2 (2t) -1= 2 (Cos^2(t)-Sin^2(t))^2 -1
(same thing as above but done twice because it's cos ^2 now)
convert sin^2
2Cos^2 (2t)-1 =2 (Cos^2 (t)+Cos^2 (t)-1)^2 -1
2 (2Cos^2(t)-1)^2 -1
2 (2Cos^2 (t)-1)(2Cos^2 (t)-1)-1
2 (4Cos^4 (t) - 2 (2Cos^2 (t))+1)-1
Distribute
8Cos^4 (t) -8Cos^2 (t) +1
Cos (4t) =8Cos^4-8Cos^2 (t)+-1
It’s A. 9 the equation is y=9x+0
Answer:
The coffee shop sells 12 cups/hour.
Step-by-step explanation:
To figure this out you would divide the amount of cups (48) by the amount of hours (4)
Substitute the values given to you into the equation:
x-(y+z)
x=9
y=3
z=2
9-(3+2)
the answer is A.
If the price is p and the quantity of bread sold is q = 400 - 100p, the average collection, in reais, depending on the price p, is given by R (p) = (400 - 100p). P
For this collection to be R $ 300.00, you must have:
(400 - 100p). p = 300 ⇔ 4p - p² = 3 ⇔ p² - 4p + 3 = 0 ⇔ p = 1 or p = 3
R $ 300.00
The current price is R $ 3.00, as R $ 300,000 / 100 = R $ 3
To maintain the collection, the price must be lowered to R $ 1.00 (R $ 0.50 <R $ 1.00 <R $ 1.50)
ANSWER: letter A
