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VMariaS [17]
3 years ago
9

Given a = 2i+j – 2k b= -1 – 7j+k Find a x b

Mathematics
1 answer:
castortr0y [4]3 years ago
7 0

Step-by-step explanation:

a = 2i + j - k

b = -1 -7j + k

a × b = (2i + j - k) (-1 + 7j + k)

-2i + 14ij + 2ik - j + 7j^2 + jk + k -7jk - k^2

-2i + 14ij + 2ik -j +7j^2 +jk - 7jk + k - k^2

-2i + 14ij + 2ik - j +7j^2 - 6jk + k - k^2

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Find the critical numbers of the function. (Enter your answers as a comma-separated list. If an answer does not exist, enter DNE
Viktor [21]

Answer:

<h2> (2, -1)</h2>

Step-by-step explanation:

Given the function f(x) = 8x³ − 12x² − 48x, <em>the critical point of the function occurs at its turning point i,e at f'(x) = 0</em>

First we have to differentiate the function as shown;

f'(x)= 3(8)x^{3-1}- 2(12)x^{2-1} - 48x^{1-1}\\  \\f'(x) = 24x^2 - 24x-48x^0\\\\f'(x) = 24x^2 - 24x-48\\\\At \ the\turning\ point\ f'(x)= 0\\24x^2 - 24x-48 = 0\\\\\\

Dividing \ through \ by \ 24\\\\x^2-x-2 = 0\\\\On \ factorizing\\\\x^2-2x+x-2 = 0\\\\x(x-2)+1(x-2) = 0\\\\(x-2)(x+1) = 0\\\\x-2 = 0 \ and \ x+1 = 0\\\\x = 2 \ and \ -1

Hence the critical numbers of the function are (2, -1)

8 0
3 years ago
Sara hina and Arslan have a total of RS 390in their wallet . Sara has Rs. 7more than Hina .Arslan has 3 times what sara has . Ho
Brums [2.3K]

Answer:Sara hina and Arslan Have RS79.4,RS 72.4 and RS238.2 respectively.

Step-by-step explanation:

Step 1

Let the amount that hina has be x

the amount that sara has be represented as  7+x

and the amount that Arslan have be represented as 3(7+x)

such that the total amount in their wallet which is 390 can be expressed as

x+7+x + 3(7+x)=390

Step 2

Solving

x+7+x +21+3x=390

5x+28=390

5x==390-28

x=362/5=72.4

Hina has RS 72.4

Sara =7+x==72.4+77= RS 79.4

Arslan =3(7+x)=3 x 79.4=RS 238.2

5 0
3 years ago
Sally bought a car for 35000 in 2017. If the car loses 5.5% semiannually, what will the value of the value of the car be at the
kumpel [21]
The value of the year at the end of 2025 will be given by:
A=P(1+r/100)^n
where:
A=future value
P=principle
r=rate
n=number of terms
hence for the data given;
p=35000
R=5.5
n=(2025-2017)*2=16
Thus
A=35000(1+5.5/100)^16
A=$82, 434. 20
5 0
3 years ago
What are all the power of threes through 1000
algol13
1000= 10^3 -- ten to the third power

assuming you mean whole numbers,

graba calculator, figure out what
1^3, 2^3 3^3 ... 9^3 are
or
1x1x1
2x2x2
3x3x3
...
9x9x9
6 0
3 years ago
3u=48-5u<br> solve for u <br> simplify your answer as much as possible
9966 [12]
U=6 u add 5u and u get 8u on the left side then u divide by 8 and u get 6 so U=6
6 0
3 years ago
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