Looks like a badly encoded/decoded symbol. It's supposed to be a minus sign, so you're asked to find the expectation of 2<em>X </em>² - <em>Y</em>.
If you don't know how <em>X</em> or <em>Y</em> are distributed, but you know E[<em>X</em> ²] and E[<em>Y</em>], then it's as simple as distributing the expectation over the sum:
E[2<em>X </em>² - <em>Y</em>] = 2 E[<em>X </em>²] - E[<em>Y</em>]
Or, if you're given the expectation and variance of <em>X</em>, you have
Var[<em>X</em>] = E[<em>X</em> ²] - E[<em>X</em>]²
→ E[2<em>X </em>² - <em>Y</em>] = 2 (Var[<em>X</em>] + E[<em>X</em>]²) - E[<em>Y</em>]
Otherwise, you may be given the density function, or joint density, in which case you can determine the expectations by computing an integral or sum.
Answer:
Divide by 3 on both sides.
Step-by-step explanation:
Original Expression: 3(x+2) = 12
Divide by 3 on both sides: x+2 = 4
Subtract 2 from both sides: x=2
Let me know if this helps!
Answer:
3:1
54:18
Step-by-step explanation:
You can divide both sides by 9 to get one ratio:
27/9:9/9
3:1
You can also multiply both sides by 2 to get another ratio:
27(2):9(2)
54:18
Answer:
10
Step-by-step explanation:
2n-6
n=8
2(8)-6
16-6
10