It would be nice if I had help with this

The set of points (1, 3), (3, 5), (4, 7) is collinear. ture or false

Mekhanik [1.2K]

(1,3)(3,5)
slope = (5-3) / (3-1) = 2/2 = 1

(3,5)(4,7)
slope = (7-5) / (4-3) = 2/1 = 2

False....they are not collinear because they have different slopes and do not lie on the same line

3 0

3 years ago

Solve the equation using the substitution u = y/x. When u = y/x is substituted into the equation, the equation becomes separable

bekas [8.4K]

Answer:

$\frac{u^2+3}{-u^3+u^2-2u}u'=\frac{1}{x}$

Step-by-step explanation:

First step: I'm going to solve our substitution for y:

$u=\frac{y}{x}$

Multiply both sides by x:

$ux=y$

Second step: Differentiate the substitution:

$u'x+u=y'$

Third step: Plug in first and second step into the given equation dy/dx=f(x,y):

$u'x+u=\frac{x(ux)+(ux)^2}{3x^2+(ux)^2}$

$u'x+u=\frac{ux^2+u^2x^2}{3x^2+u^2x^2}$

We are going to simplify what we can.

Every term in the fraction on the right hand side of equation contains a factor of $x^2$ so I'm going to divide top and bottom by $x^2$ :

$u'x+u=\frac{u+u^2}{3+u^2}$

Now I have no idea what your left hand side is suppose to look like but I'm going to keep going here:

Subtract u on both sides:

$u'x=\frac{u+u^2}{3+u^2}-u$

Find a common denominator: Multiply second term on right hand side by $\frac{3+u^2}{3+u^2}$ :

$u'x=\frac{u+u^2}{3+u^2}-\frac{u(3+u^2)}{3+u^2}$

Combine fractions while also distributing u to terms in ( ):

$u'x=\frac{u+u^2-3u-u^3}{3+u^2}$

$u'x=\frac{-u^3+u^2-2u}{3+u^2}$

Third step: I'm going to separate the variables:

Multiply both sides by the reciprocal of the right hand side fraction.

$u' \frac{3+u^2}{-u^3+u^2-2u}x=1$

Divide both sides by x:

$\frac{3+u^2}{-u^3+u^2-2u}u'=\frac{1}{x}$

Reorder the top a little of left hand side using the commutative property for addition:

$\frac{u^2+3}{-u^3+u^2-2u}u'=\frac{1}{x}$

The expression on left hand side almost matches your expression but not quite so something seems a little off.

5 0

3 years ago

What is the volume of the composite figure? A rectangular prism is positioned vertically; at the top it joins another rectangula

Phantasy [73]

V = V 1 + V 2 + V 3 =
= 4² · 8 + 4² · 12 + 4² ·8 =
= 4² · ( 8 + 12 + 8 ) =
= 16 · 28 = 448
Answer:
The volume of the composite figure is 448 yd³.

5 0

4 years ago

The conjugate of (2+i)²/3+i, in the form of a+ib, is

goblinko [34]

Given that

(2+i)²/(3+i)

On multiplying both numerator and the denominator with (3-i) then

⇛ [(2+i)²/(3+i)]×[(3-i)/(3-i)]

⇛ [(2+i)²(3-i)]/[(3+i)(3-i)]

⇛ [(2+i)²(3-i)]/[(3²-i²)

⇛ [(2+i)²(3-i)]/(9-i²)

⇛ [(2+i)²(3-i)]/[9-(-1)]

Since ,i² = -1

⇛ [(2+i)²(3-i)]/(9+1)

⇛ [(2+i)²(3-i)]/10

⇛ [{2²+i²+2(2)(i)}(3-i)]/10

⇛ (4+i²+4i)(3-i)/10

⇛ (4-1+4i)(3-i)/10

⇛ (3+4i)(3-i)/10

⇛ (9-3i+12i-4i²)/10

⇛ (9+9i-4(-1))/10

Since, i² = -1

⇛(9+9i+4)/10

⇛(13+9i)/10

⇛ (13/10)+ i (9/10)

We know that

The conjugate of a+ib is a-ib

So,

The conjugate of (13/10)+ i (9/10) is

(13/10)-i(9/10) ⇛ (13/10)+i (-9/10)

Answer:-The conjugate of (13/10)+ i (9/10) is (13/10)+i (-9/10)

Additional comment:

The conjugate of a+ib is a-ib and
i = -1
(a+b)² = a²+2ab+b² • (a+b)(a-b)=a²-b² •(a-b)²=a²-2ab+b².

5 0

2 years ago

Simplify: (5x2 - 4x + 7) – (2x2 – 3x – 4)

Kamila [148]

The answer is b. Hope this helps!!

4 0

3 years ago