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2 years ago

If a=2i-3j-k and b=i+4j+2k what us ab

Mathematics

1 answer:

Masteriza [31]2 years ago

8 0

Answer:

2i²+5ij+3ik-12j²-10jk-2k²

Step-by-step explanation:

a=2i-3j-k

b=i+4j+2k

ab = (2i-3j-k) (i+4j+2k)

Multiply both bracket by expanding the bracket

2i(i+4j+2k)-3j(i+4j+2k)-k(i+4j+2k)

Multiply

2i²+8ij+4ik-3ij-12j²-6jk-ik-4jk-2k²

Collect like terms

2i²+8ij-3ij+4ik-ik-12j²-6jk-4jk-2k²

2i²+5ij+3ik-12j²-10jk-2k²

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Olivia is planning to study for 8 hours. she has to spend studying English twice the time she needs for science and the time she

vaieri [72.5K]

Answer:

science = $\frac{4}{3} \ hours$

English = $\frac{8}{3} \ hours$

Math = 4 hours

Step-by-step explanation:

let the number of hours spend on science = x

Hence the number of hours on English will be = 2x

Given that the number of hours spend on science is one third of the time spend on maths. Hence the time spend on math is 3 times that of the time spend on science. That the time spend on maths is = 3x

Hence the total time to study is

x+2x+3x

which is given as 8 hours

Hence

x+2x+3x =8

6x=8

dividing both sides by 6

$\frac{6x}{6}=\frac{8}{6}$

$x=\frac{8}{6}$

$x=\frac{4}{3}$

Hence the number of hours foe studying science = $\frac{4}{3}$

Number of hours to study English = $\frac{4}{3} \times 2$ = $\frac{8}{3}$

Number of hours to study Math= $\frac{4}{3} \times 3$ = $4$

5 0

3 years ago

If 1 pound of candy is 3.50 how much candy can you get with one dollar?

polet [3.4K]

Answer:

Step-by-step explanation:

16 divided by $3.50 = 4.5

4 0

3 years ago

Read 2 more answers

Help me, please! I will mark the brainiest! ANY OFF TOPIC ANSWER WILL BE DELETED!

Lynna [10]

The anwser is 3x-5 yuhhhhhhhhhhhhhhhhh

4 0

3 years ago

Tbh I'm just too lazy to actually do this and my head hurts from the rest of my school work so I'm just asking it on here -2/5 +

Leto [7]

Answer:

1/10

Step-by-step explanation:

-2/5 + 1/2

-4/10 + 5/10

-4 + 5/10

= 1/10

Hope this helps!

6 0

3 years ago

Read 2 more answers

14 kg of apples cost $154.how much would 16kg cost

ankoles [38]

We can set up a proportion, and let x be the amount 16kg would cost: 14/154=16/x. We simplify 14/154 = 1/11. Next, we cross-multiply to get (1)(x)=(16)(11), so x=176. Therefore, 16kg of apples cost $176.
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Hope this helps!

4 0

2 years ago

Read 2 more answers

If a=2i-3j-k and b=i+4j+2k what us ab​

If a=2i-3j-k and b=i+4j+2k what us ab