Trigonometric Functions
Logarithms
Rational Equations
The Unit Circle
Vocabulary
400

Find sin Θ :

Answer:

sin Θ = 4/5

Explanation:

sin= opposite/hypotenuse

Opposite of Θ  is 8 and the hypotenuse is 10

So 8/10= 4/5

sin Θ = 4/5

400

Solve:

Log21 = x

Answer:
x = 0

Explanation: 

Log21 = 2x = 1 and Log21 = x

Anything raised to the zero is 1

so x = 0

400

Simplify:

2x-1/x2+2 - 4x+4/x2+2

Answer:

-2x-5/x2+2

Explanation:

(2x - 1)-(4x + 4)/x2+2

= -2x-5/x2+2

400

Convert to Radians:

2 degrees

Answer:

pi/90 radians

Explanation:
(2 degrees)(pi/180) = 2pi/180 = pi/90 radians

400

The unit used for angle measurement.

What is degrees?

800

Find Cos θ :

Answer:

Tan θ = 12/13

Explanation:

Cos = adjacent/hypotenuse

We first must find the hypotenuse using pythagorean theorum.

52 + 122 = x2

25 + 144 = 169

square root of 169 = 13

Cos θ = 12/13

800

Solve:

log5x = 2

Answer:

x=25

Explanation:

52 = x

52 = 25

x=25

800

Solve the equation and find the solution(s) for:

x + 8/x = 6

Answer:

x=4      x=2

Explanation:

(x + 8/x = 6)x

x2 + 8 =6x

x2 - 6x + 8 =0

(x - 4)(x - 2) =0

x=4    x=2

Check for extraneous solutions

4 + 8/4 =6

2 + 8/2 =6

800

Convert to degrees:

pi/2 radians

Answer:

90 degrees

Explanation:

(pi/2)(180/pi) = 180/2 = 90 degrees

800

The angle formed by the line of sight and the horizontal plane for an object below the horizontal.

What is the angle of depression?

1200

From a point on the ground 47 feet from the foot of a tree, the angle of elevation of the top of the tree is 35º. Find the height of the tree to the nearest foot.

*calculator required*


Answer:

33 feet

Explanation:

To get x, we have to do Tan 35 degrees. 

Tan 35 = x/47

Tan 35 · 47 = x

x ≈ 33

1200

Solve:

log3(x - 5) = 2

Answer:

x = 14

Explanation:

32 = x - 5

9= x - 5

9 + 5 = x

x=14

1200

Solve the equation and find the solution(s):

6x/x+4 = 7x+4/x+4

Answer:

NO SOLUTIONS

Explanation:

(7x + 4)(x + 4)/x+4 = 6x(x + 4)/x+4

7x + 4 = 6x

7x -6x = -4

x= -4

Check for extraneous solutions:

6(-4)/-4+4 = 7(-4)+4/-4+4

You can't have 0 in the denominator so -4 would not work. Therefore, there is no solution.

1200

Convert to degrees:

11pi/12



Answer:

165 degrees

Explanation:

(11pi/12)(180/pi) =1980/12 = 165 degrees

1200

The exponent to which a specified base is raised to obtain a given value.

What is a logarithm?

1600

Find cosecant of 45 (the bottom one):

Answer:

 √2

Explanation:

Cosecant= hypotenuse/opposite

sin 45 = a/4√2

sin 45 · 4√2 = a

 a = 4

csc 45 = 4√2/4 =  √2


1600

Solve:

log4x2 = 7

Answer:

x = 128

Explanation:

2 · log4x = 7

log4x = 7/2

47/2 = x

x = 128

1600

Solve the equation and find the solution(s) for:

x+2/x-3 + x/5 = 5/x-3

Answer:

x= -5

Explanation:

(x+2/x-3 + x/5 = 5/x-3) · 5(x - 3)

5(x + 2) + x(x - 3) = 25

5x + 10 + x2 - 3x = 25

x2 + 2x - 15 =0

(x + 5)(x - 3) =0

x= -5     x=3

Check for extraneous solutions

-5+2/-5-3 +-5/5 = 5/-5-3

3/8 + -1 = 5/-8

3+2/3-3 + 3/5 = 5/3-3

There can't be a 0 in the denominator so 3 is not a solution

1600

Convert to Radians:

396 degrees

Answer:

11pi/5 radians

Explanation:

(396 degrees)(pi/180) = 396pi/180 = 11pi/5 radians

1600

A line that the graph of a rational function approaches as it moves to infinity.

What is an asymptote?

2000

Find all 6 basic trig functions:

Answer:

sin θ = √7/4       cos θ = 3/4      tan θ = √7/3

csc θ = 4√7/7     sec θ = 4/3      cot θ = 3√7/7

Explanation:

First, we must use pythagorean theorum to find the missing side of the triangle

92 + x2 = 122

81 + x2 = 144

144 - 81 = x2

63 = x2

3√7 = x

Find all 6 basic trig functions:

Sin θ = 3√7/12 = √7/4

Cos θ = 9/12 = 3/4

Tan θ = 3√7/9 = √7/3

csc θ = 12/3√7 = (12/3√7)(√7/√7) = 12√7/3·7

=12√7/21 = 4√7/7

sec θ = 12/9 = 4/3

cot θ = 9/3√7 = (9/3√7)(√7/√7) = 9√7/ 3·7

= 9√7/21 = 3√7/7

2000

Solve:
logx + log(x + 9) = 1

Answer:

x = 1

Explanation:

Since no log is written we assume it has a common log of 10

log10x + log10(x + 9) = 1

logx(x + 9) = 1

log(x2 + 9x) = 1

101 = x2 + 9x

0= x2 + 9x - 10

0 = (x + 10)(x - 1)

x= -10     x= 1

You can't have a negative with logarithms so the only solution is x = 1

2000

Simplify:

6x/2x2+10x · 3x2-75/x2-3x-10 ÷ 3x2+12-63/x2+9x+14

Answer:

3/(x - 3)

Explanation:

Factor: 6x/2x(x + 5) · 3(x2 - 25)/(x - 5)(x + 2) · (x + 7)(x + 2)/3(x2 + 4x - 21)

= 6x/2x(x + 5) · 3(x + 5)(x + 5)/(x - 5)(x + 2) · (x + 7)(x + 2)/3(x + 7)(x - 3)

= 6x/2x(x + 5) · 3(x + 5)/(x + 2) · (x + 2)/3(x - 3)

= 3 · 3 ·  1/3(x - 3)

= 3/(x-3)

2000

Convert to degrees:

23pi/4

Answer:

1035 degrees

Explanation:

(23pi/4)(180/pi) = 4140/4 = 1035 degrees

2000

A solution of an equation derived from an original equation that is not a solution of the original equation.

What is an extraneous solution?