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# ?

• ### Two CE Maths questions

1. Solve the equation 2sin^2@ + 7sin@ + 3 = 0, where 0 =/< @ =/< 360.

2. Let f(x)=x^3+kx^2-kx+4, where k is a constant. If f(x) is divisible by x-2, find the remainder when f(x) is divided by x-4.

I suspect that the answers provided are wrong, so I'm posting the questions here. Thanks!!! :)

1 個解答數學1 十年前
• ### Functions and graphs

Graph of y=f(x)=2x^2+(k+1)x+2 touches the x-axis on one point only.

Find the value(s) of k.

我計到k=3 or -5

但係老師個答案只有k= -5

點解k=3要reject?

1 個解答數學1 十年前
• ### if -3 is a root of the equation x^2+(13+k)x+k=0...

if -3 is a root of the equation x^2+(13+k)x+k=0, find

a) the value of k

b) the other root of the equation.

Thanks :)

3 個解答數學1 十年前
• ### Mechanics (bungy jumping)

A man with mass 70kg is is bungy jumping from 200m above a river. Length of cord used is 50m

1 Calculate the velocity when the cord is just stretched

2 The man stops when he just reached river, calculate the extension and the energy stored by the elastic cord

3 Given that energy stored in the cord =(1/2)kx^2, k is the force constant of cord and x the extension of cord (force constant=force per unit extension) Find:

i) k

ii) acc. of the man the moment when he reaches water

1 個解答其他 - 科學1 十年前
• ### A question on the topic Heat

c of water =4200, l=2.26x10^6

a) Calculate the energy neeed to generate 500g of steam from the water at 25C.

b) input of power is 600W. effeiciency of steamer is 75%. find the min. time to generate 500g of steam from water at 25C.

c) cost of electricityis \$0.85 per kWh, caculate the cost to generate 500g of steam from water at 25C, using the result from (b).

Thanks! :)

1 個解答其他 - 科學1 十年前
• ### Sailor Uranus(天王遙)和Sailor Neptune(海王滿/美智留)為了甚麼而死?

在 198話中,Sailor Uranus 和 Sailor Neptune 都死了.

Sailor Moon在她們死時還哭著責怪自己之前沒有相信她們.

究竟是甚麼一會事?

為何Sailor Uranus 和 Sailor Neptune會曾經被認為是背叛者?

她們又真的曾出賣過 Sailor Moon等人嗎?

198話:

第一部分 第二部分 第三部分 第四部分 1 個解答漫畫及動畫1 十年前
• ### 下列的那些金屬是包含於焊料(solder)中?

(1) 銅 copper

(3) 鐵 iron

A. (1) only

B. (2) only

C. (1) and (3) only

D. (2) and (3) only

已知答案是 B,但從何得知?

註:這是會考程度的問題.

2 個解答化學1 十年前