| u | = √(2² + (-1²)) = √5
| v | = √ ( 1² + (-8)² = √65
cos (u,v) = ( u * v ) / (| u | * | v |) =
(2 * 1 + ( -1 ) * ( - 8 )) / √5 √ 65 = (2 + 8) / √5 √65 = 10 / (√5 √ 65 )
The length of a larger diagonal:
d 1² = | u |² + 2 |u| |v| + | v |² = 5 + (2 √5 √65 * 10 / √5 √65 )+65
d 1² = 70 + 20 = 90
d 1 = √ 90 = 3√10
d 2² = 70 - 20 = 50
d 2 = √50 = 5√2
Answer:
The lengths of the diagonals are: 3√10 and 5√2 .
Answer:
Choice B, 10 inch pizza to himself
Step-by-step explanation:
1. Half of 16 inch pizza= 8 inch
2. 10 inch pizza to himself= well, 10 inch
10>8
Answer:
33/20
Step-by-step explanation:
1/12 - 1/15 = 5/60 - 4/60 = 1/60
d = 1/60
a_n = a_1 + d(n - 1)
a_11 = 1/15 + (1/60)(11 - 1)
a_11 = 1/15 + 1/6
a_11 = 4/60 + 10/60
a_11 = 14/60
a_11 = 7/30
a_12 = 14/60 + 1/60
a_12 = 15/60
a_12 = 1/4
s_n = n(a_1 + a_n)/2
s_11 = 11(1/15 + 7/30)/2
s_11 = 11(2/30 + 7/30)/2
s_11 = 11(9/30)/2
s_11 = 99/60
s_11 = 33/20
Answer:
B and C work. A and D do not.
Step-by-step explanation:
This is one of those questions that you have to go through each answer to see what the results are. You don't have to go far to eliminate A and D so let's do that first.
A]
5n + 6
Let n = 1
5(1) + 6
5 + 6= 11
However there is trouble beginning with n = 2
5*2 + 6
10 + 6
16 All you need is one wrong answer and the choice is toast. So A won't work.
================
Try D
6(n - 1)+ 5
n=0
6*(-1) + 5
-6 + 5
- 1
And D has been eliminated with just 1 attempt. n= 2 or n = 1 would be even worse. D is not one of the answers.
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B
Let n = 1
6(1) + 5
6 + 5
11 The first term works.
n = 2
6*(2) + 5
12 + 5
17 and n = 2 works as well. Just in case it is hard to believe, let's try n = 3 because so far, everything is fine.
n = 3
6*(3) + 5
18 + 5
23 And this also works. I'll let you deal with n = 4
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C
n = 0
6(0 + 1) + 5
6*1 + 5
6 + 5
11
n = 1
6(1 + 1) + 5
6*2 + 5
12 + 5
17 which works.
So C is an answer.
Answer: (4)
Step-by-step explanation:
The parts listed in the congruence statements don't correspond, so they aren't necessarily congruent.
