What is x cube + x square

Khan academy how to solve equations with fractions and mixed numbers

Rufina [12.5K]

Generally, you are told to approach these by "clearing fractions". That is, you generally multiply the equations by the least common denominator so all fractions and mixed numbers become integers.

Alternatively, you can simply do the arithmetic using the numbers given. You learned a long time ago how to add, subtract, multiply, and divide mixed numbers and fractions. Do these operations as necessary to solve the equations.

8 0

3 years ago

Which is true about the solution to the system of inequalities shown? y less than or equal to 1/3x-1 and y less than or equal to

tekilochka [14]

Y≤x/3-1 AND y≤x/3-3

So for BOTH inequalities to be true:

y≤x/3-3

4 0

3 years ago

A square has a perimeter of 36 millimeters.<br> What is the area of the square?

Nana76 [90]

Answer:

81 mm²

Step-by-step explanation:

3 0

3 years ago

(1.)What is the value of 35−3m , when m = 4?

Len [333]

(1.) 35-3m
m= 4

35-3m
= 35-3(4)
= 35-12 (do the multiple/division first before doing the addition/subtraction)
= 23

C. 23

(2.) 1 + x ÷ 5
x = 80

1 + x ÷ 5
= 1+80÷5
= 1+16
= 17

(3.) mx-y
m=5, x=3, and y=8

mx-y
= 5(3)-8
= 15-8
= 7

(4.) 3a+15+bc−6
a=7, b=3, and c=15

3a+15+bc-6
= 3(7)+15+3(15)-6
= 21+15+45-6
= 75

4 0

3 years ago

Trigonometry help!! - double angle formulae

ivolga24 [154]

Answer:

The two rules we need to use are:

Sin(a + b) = sin(a)*cos(b) + sin(b)*cos(a)

cos(a + b) = cos(a)*cos(b) - sin(a)*sin(b)

And we also know that:

sin^2(a) + cos^2(a) = 1

To solve the relations, we start with the left side and try to construct the right side.

a) Sin(3*A) = sin (2*A + A) = sin(2*A)*cos(A) + sin(A)*cos(2*A)

sin(A + A)*cos(A) + sin(A)*cos(A + A)

(sin(A)*cos(A) + sin(A)*cos(A))*cos(A) + sin(A)*(cos(A)*cos(A) - sin(A)*sin(A))

sin(A)*cos^2(A) + sin(A)*cos^2(A) + sin(A)*cos^2(A) - sin^3(A)

3*sin(A)*cos^2(A) - sin(A)*sin^2(A)

sin(A)*(3*cos^2(A) - sin^2(A))

Now we can add and subtract 4*sin^3(A)

sin(A)*(3*cos^2(A) - sin^2(A)) + 4*sin^3(A) - 4*sin^3(A)

sin(A)*(3*cos^2(A) + 3*sin^2(A)) - 4*sin^3(A)

sin(A)*3*(cos^2(A) + sin^2(A)) - 4*sin^3(A)

3*sin(A) - 4*sin^3(A)

b) Here we do the same as before:

cos(3*A) = 4*cos^3(A) - 3*cos(A)

We start with:

Cos(2*A + A) = cos(2*A)*cos(A) - sin(2*A)*sin(A)

= cos(A + A)*cos(A) - sin(A + A)*sin(A)

= (cos(A)*cos(A) - sin(A)*sin(A))*cos(A) - ( sin(A)*cos(A) + sin(A)*cos(A))*sin(A)

= (cos^2(A) - sin^2(A))*cos(A) - sin^2(A)*cos(A) - sin^2(A)*cos(A)

= cos^3(A) - 3*sin^2(A)*cos(A)

= cos(A)*(cos^2(A) - 3*sin^2(A))

now we subtract and add 4*cos^3(A)

= cos(A)*(cos^2(A) - 3*sin^2(A)) + 4*cos^3(A) - 4*cos^3(A)

= cos(A)*(-3*cos^2(A) - 3*sin^2(A)) + 4*cos^3(A)

= cos(A)*(-3)*(cos^2(A) + sin^2(A)) + 4*cos^3(A)

= -3*cos(A) + 4*cos^3(A)

8 0

3 years ago