Answer:
...
Step-by-step explanation:
The magnitude of the vector is

the component form is
<2,5>
Answer:
The ratio of the first term to the common difference is 1 : 2
Step-by-step explanation:
The rule of the sum of the AP is
, where
a is the first number
d is the common difference
n is the position of the number
∵
= 4 ×
⇒ (1)
→ Find
and 
∵ In
n = 10
∴ ![S_{10}=\frac{10}{2}[2a+(10-1)d]](https://tex.z-dn.net/?f=S_%7B10%7D%3D%5Cfrac%7B10%7D%7B2%7D%5B2a%2B%2810-1%29d%5D)
∴ ![S_{10}=5[2a+9d]](https://tex.z-dn.net/?f=S_%7B10%7D%3D5%5B2a%2B9d%5D)
∴
= 10a + 45d ⇒ (2)
∵ In
n = 5
∴ ![S_{5}=\frac{5}{2}[2a+(5-1)d]](https://tex.z-dn.net/?f=S_%7B5%7D%3D%5Cfrac%7B5%7D%7B2%7D%5B2a%2B%285-1%29d%5D)
∴ ![S_{5}=2.5[2a+4d]](https://tex.z-dn.net/?f=S_%7B5%7D%3D2.5%5B2a%2B4d%5D)
∴
= 5a + 10d ⇒ (3)
→ Substitute (2) and (3) in (1)
∵ 10a + 45d = 4[5a + 10d]
∴ 10a +45d = 20a + 40d
→ Subtract 40d from both sides
∴ 10a + 45d - 40d = 20a + 40d - 40d
∴ 10a + 5d = 20a
→ Subtract 10a from both sides
∴ 10a - 10a + 5d = 20a - 10a
∴ 5d = 10a
→ Divide both sides by 5
∴ d = 2a
→ That means d is twice a or a is half d
∴ a : d = 1 : 2
The ratio of the first term to the common difference is 1 : 2
Answer:
7) no 8) no 9) no 10)yes 11) yes 12) yes 13) k=42 14) c=30 15)a=42
Step-by-step explanation:
It would be 270 cm given that the top chape is 72cm and the bottom rect. is 198 cm.