jane didcounted amount : 950 *30:100 = 285 ( dollars)

phân tích n^3 + 3n^2 + 2n thảnh n.(n+1).(n+2) chia hết cho 6 vì chia hết cho 2 và 3                                                                                chia hết cho 15 là chia hết cho 3 với 5 nha

2) a=-(b+c)=> a²=(-(b+c))²

a²-b²-c²=2bc

(a²-b²-c²)²=(2bc)²

a⁴+b⁴+c⁴-2a²b²+2b²c²-2a²c²=4b²c²

a⁴+b⁴+c⁴=2a²b²+2b²c²+2a²c²

2(a⁴+b⁴+c⁴)=(a²+b²+c²)²

Vì a²+b²+c²=14 nên 2(a⁴+b⁴+c⁴)=196

=>a⁴+b⁴+c⁴=98

a )   A = 84 − x + 84 − 23 ;       A = 84 − x − 84 − 23       A = 84 − 84 − x − 23       A = − x − 23 b )   B = 39 + x − 15 − 39 ;       B = 39 + x − 15 − 39       B = 39 − 39 + x − 15       B = x − 15

a, 84 + (-13)  - (-29)

=   84 - 13 + 29

= 71 + 29

= 100

b, (-15).2 - 120 : 6 + 84 : (-4)

 = -30 - 20  - 21

= - (30 + 20 + 21)

=  - 71

Nhanh đi bạn

Refer:

The line graph depicts a comparison between the consumption of three categories of fast food eaten by Australian teenagers over 25 year period from 1975 to 2000. In general, there was a gradual fall in consuming fish and chips while pizza and hambergers had an opposite trend.

As the graph shows, the amount of fish and chips peaked at 100 times per year in 1975. Then, there was a fluctuation during period from 1975 to 1985 before standing at about 95 times. Following this, the need for fish and chips significantly decreased to a low of nearly 40 times in 2000.

By contrast, pizza and hamburgers became more popular and their expenditure substantially went up. Looking at the details, pizza’s consumption rised steadily from about 2 times in 1975 to over 80 times in 1995, though its figure leveled off from 1995 to 2000. wise, there was a considerable increase of hamburgers’ rate from 5 times to approximately 83 times. This rise was noeable between 1975 and 1985 but the growth slowed during the remaining period.

Vai! day ma la tieng anh lop 1 ha?