Base case: if <em>n</em> = 1, then
1² - 1 = 0
which is even.
Induction hypothesis: assume the statement is true for <em>n</em> = <em>k</em>, namely that <em>k</em> ² - <em>k</em> is even. This means that <em>k</em> ² - <em>k</em> = 2<em>m</em> for some integer <em>m</em>.
Induction step: show that the assumption implies (<em>k</em> + 1)² - (<em>k</em> + 1) is also even. We have
(<em>k</em> + 1)² - (<em>k</em> + 1) = <em>k</em> ² + 2<em>k</em> + 1 - <em>k</em> - 1
… = (<em>k</em> ² - <em>k</em>) + 2<em>k</em>
… = 2<em>m</em> + 2<em>k</em>
… = 2 (<em>m</em> + <em>k</em>)
which is clearly even. QED
R + b = 146. Supposing that b=r+28,
r + (r+28) = 146, or 2r + 28 = 146.
Simplifying: 2r = 118. Then r = 59, and b = r+28 = 59+28 = 87 blue marbles
Answer:
400
Step-by-step explanation:
The computation of the sample size needed is shown below:
Since at the sample size of 200 there is a standard deviation of 0.08
But when the standard deviation is 0.04 so the sample size is 400
As sample standard deviation would be inversely proportional to the square root of the sample size
Answer:
x³ - 6x² + 18x - 10
Step-by-step explanation:
(f - g)(x) = f(x) - g(x)
= x³ - 2x² + 12x - 6 - (4x² - 6x + 4)
= x³ - 2x² + 12x - 6 - 4x² + 6x - 4 ← collect like terms
= x³ - 6x² + 18x - 10
Answer:
x=1.2
Step-by-step explanation:
2(5x-4)=4
distribute 2 to 5x and -4
10x-8=4
add 8 to negative 8 and 4
10x=12
now divide both sides by 10
10x/10= 12/10
x=1.2
