Answer:(a)x^2+2y^2=2
(b)In the attached diagram
Step-by-step explanation:Step 1: Multiply both equations by t
xt=t(cost -sint)\\ty\sqrt{2} =t(cost +sint)
Step 1: Multiply both equations by t
xt=t(cost -sint)\\ty\sqrt{2} =t(cost +sint)
Step 2:We square both equations
(xt)^2=t^2(cost -sint)^2\\(ty)^2(\sqrt{2})^2 =t^2(cost +sint)^2
Step 3: Adding the two equations
(xt)^2+(ty)^2(\sqrt{2})^2=t^2(cost -sint)^2+t^2(cost +sint)^2\\t^2(x^2+2y^2)=t^2((cost -sint)^2+(cost +sint)^2)\\x^2+2y^2=(cost -sint)^2+(cost +sint)^2\\(cost -sint)^2+(cost +sint)^2=2\\x^2+2y^2=2 hopes this helps
Answer:
f(r) = 2πr
Step-by-step explanation:
You know the formula for circumference in terms of radius is ...
C = 2πr
You are being asked to write this as a function named "f". That will be ...
f(r) = 2πr
You are right. 5 is correct.
I is C because you use the pythag theorem
Answer:
Step-by-step explanation:
You can split the coins into 3 groups, each of them has 3 coins. Weigh group 1 vs group 2, if one is lighter, that group has the fake coin. If both groups weigh the same, then group 3 has the fake coin.
Continue to split the group that has the fake coin into 3 groups, each group has 1 coin. Now apply the same procedure and we can identify the fake coin.
Total of scale usage is 2
b) if you have 
coins then you can apply the same approach and find the fake coin with just n steps. By splitting up to 3 groups each step, after each step you should be able to narrow down your suspected coin by 3 times.
Step 1: you narrow down to group of 
coins
Step 2: you narrow down to group of 
coins
Step 3: you narrow down to group of 
coins
...
Step n: Step 1: you narrow down to group of 
coin
