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2 years ago

I WILL GIVE BRAINLIST AND 5 STARS Show that (2x + i)(2x – i) = 4x² + 1

Mathematics

1 answer:

sladkih [1.3K]2 years ago

8 0

Answer:

see below

Step-by-step explanation:

(2x + i)(2x – i)

FOIL

first 2x*2x =4x^2

outer -i * 2x = 2x i

inner i * 2x = 2x i

last i * -i = -i^2 and i^2 = -1 so - (i^2 ) = - (-1) = 1

Add together

4x^2 + 2xi -2x i +1

Combine like terms

4x^2 +1

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Find the unit vector in the direction of u = (-3,2).

DENIUS [597]

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(-3,2)\qquad \stackrel{unit~vector}{\implies }\qquad \left( \cfrac{-3}{\sqrt{(-3)^2+2^2}}~~,~~\cfrac{2}{\sqrt{(-3)^2+2^2}} \right)
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$\bf \textit{and now let's \underline{rationalize} the denominator for each}
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7 0

3 years ago

Sm1 please help me w this question!!!

Lady_Fox [76]

Answer:

The answer is A, (1,2).

Step-by-step explanation:

Hope this helps!

8x-4(x+1) = 0

x =1

y = 1 + 1

y = 2

(x,y) = (1,2)

2 = 1 + 1

8 x 1 - 4 x 2 = 0

Simplify

2 = 2

0 = 0

Solution = (1 , 2)

6 0

2 years ago

True, false, or open 4y+8=6y+3

Soloha48 [4]

Answer:

its open you never know tho

Step-by-step explanation:

3 0

3 years ago

What is 4x plus 6 plus 3 equals seventeen

Allushta [10]

The answer is 3.

the equation: 4x+6+3=17
4x+9=17
subtract 9 from both sides
4x=12
x=3

check by inserting 3 as x into the original equation

4*3+6+3=17

hope this helps!

7 0

3 years ago

Use the distance formula to find the distance, to the nearest tenth, from S(5,-4) to W(-3,7)

natali 33 [55]

Answer:

Distance (d) =13.6

Step-by-step explanation:

$d=\sqrt{\left(x_2-x_1\right)^2+\left(y_2-y_1\right)^2}\\\\(5,-4)=(x_1,y_1)\\(-3,7)=(x_2,y_2)\\\\d=\sqrt{\left(-3-5\right)^2+\left(7-\left(-4\right)\right)^2}\\\\d=\sqrt{(-3-5)^2+(7+4)^2}\\\\d=\sqrt{(-8)^2+(11)^2}\\\\d=\sqrt{64+121}\\\\d=\sqrt{185} \\\\d = 13.60147\dots \\\\\\d =13.6$

7 0

2 years ago