BackPrecalculus Test 1 Review – Step-by-Step Study Guidance
Study Guide - Smart Notes
Tailored notes based on your materials, expanded with key definitions, examples, and context.
Q1. Arc Length: Find the missing quantity.
(a) Given: m, m, radians
Background
Topic: Arc Length of a Circle
This question tests your understanding of the relationship between arc length, radius, and central angle (in radians).
Key formula:
Where:
= arc length
= radius
= central angle (in radians)
Step-by-Step Guidance
Write the formula for arc length: .
Plug in the known values: .
To solve for , divide both sides by $7$.
Try solving on your own before revealing the answer!
(b) Given: m, , radians
Background
Topic: Arc Length of a Circle
This part asks you to solve for the radius when given arc length and central angle.
Key formula:
Step-by-Step Guidance
Start with the formula: .
Plug in the known values: .
To solve for , divide both sides by $7$.
Try solving on your own before revealing the answer!
Q2. Area of a Sector: Find the missing quantity.
(a) Given: sq ft, , radians
Background
Topic: Area of a Sector
This question tests your ability to use the formula for the area of a sector of a circle.
Key formula:
Step-by-Step Guidance
Write the formula: .
Plug in the known values: .
Multiply both sides by $2$ to eliminate the fraction.
Divide both sides by to solve for .
Take the square root of both sides to solve for .
Try solving on your own before revealing the answer!
(b) Given: sq ft, ft,
Background
Topic: Area of a Sector (Angle in Degrees)
This part requires you to convert degrees to radians before using the area formula.
Key formula:
(with in radians)
Step-by-Step Guidance
Convert to radians using .
Plug the converted angle and into the area formula: .
Simplify the expression to set up for calculation.
Try solving on your own before revealing the answer!
Q3. Angle Conversion
(a) Convert radians to degrees.
Background
Topic: Radian-Degree Conversion
This question tests your ability to convert between radians and degrees.
Key formula:
Step-by-Step Guidance
Write the conversion formula: .
Plug in for radians.
Simplify the expression to set up for calculation.
Try solving on your own before revealing the answer!
(b) Convert to radians.
Background
Topic: Degree-Radian Conversion
Key formula:
Step-by-Step Guidance
Write the conversion formula: .
Plug in $84$ for degrees.
Simplify the expression to set up for calculation.
Try solving on your own before revealing the answer!
Q4. Trigonometric Functions: Given , is acute. Find the remaining five trigonometric functions.
Background
Topic: Trigonometric Functions and Identities
This question tests your understanding of the relationships between the six trigonometric functions.
Key terms and relationships:
Other functions:
Step-by-Step Guidance
Express in terms of : .
Use to solve for .
Find and using and .
Find using .
Try solving on your own before revealing the answer!
Q5. The point is on the terminal side of an angle in standard position. Find the exact value of each of the six trig functions of .
Background
Topic: Trigonometric Functions from a Point
This question tests your ability to use the coordinates of a point to find all six trigonometric functions.
Key terms and formulas:
(distance from origin)
Reciprocal functions:
Step-by-Step Guidance
Calculate .
Find and .
Find .
Find as reciprocals of .
Try solving on your own before revealing the answer!
Q6. Find the exact value of the following:
(a)
Background
Topic: Evaluating Trigonometric Functions at Given Angles
This question tests your ability to evaluate trigonometric functions for angles outside the standard interval.
Key steps:
Find a coterminal angle between $0 by adding or subtracting multiples of .
Recall .
Step-by-Step Guidance
Find a coterminal angle for by adding as needed.
Evaluate at the coterminal angle.
Take the reciprocal to find .
Try solving on your own before revealing the answer!
(b)
Background
Topic: Evaluating Trigonometric Functions
Key steps:
Find a coterminal angle between $0.
Evaluate at that angle.
Step-by-Step Guidance
Subtract as needed to find a coterminal angle for .
Evaluate at the coterminal angle.
Try solving on your own before revealing the answer!
Q7. Given and , find .
Background
Topic: Trigonometric Identities and Signs
This question tests your ability to use one trigonometric function to find another, considering the sign of the function.
Key relationships:
Use the Pythagorean identity:
Step-by-Step Guidance
Let and for some (since ).
Use the Pythagorean identity to solve for .
Find and then .
Try solving on your own before revealing the answer!
Q8. Graph at least two cycles of the function .
Background
Topic: Graphing Trigonometric Functions
This question tests your ability to graph cosine functions with amplitude and vertical shift.
Key features:
Amplitude:
Vertical shift:
Period:
Step-by-Step Guidance
Identify the amplitude, period, and vertical shift.
Sketch the midline at .
Mark the maximum and minimum values using amplitude and shift.
Plot key points for two cycles and sketch the curve.
Try sketching the graph before checking the answer!
Q9. Graph at least two cycles of the function .
Background
Topic: Graphing Sine Functions with Transformations
Key features:
Amplitude: $1-1$)
Period:
Reflection over the x-axis due to the negative sign
Step-by-Step Guidance
Calculate the period: .
Note the amplitude and reflection.
Mark key points for two cycles and sketch the curve.
Try sketching the graph before checking the answer!
Q10. Graph at least two cycles of the function .
Background
Topic: Graphing Cosine Functions with Phase Shift
Key features:
Amplitude: $1$
Period:
Phase shift: left by
Step-by-Step Guidance
Identify the amplitude, period, and phase shift.
Shift the basic cosine graph left by .
Plot key points for two cycles and sketch the curve.
Try sketching the graph before checking the answer!
Q11. Graph at least two cycles of the function .
Background
Topic: Graphing Secant Functions
Key features:
Secant is the reciprocal of cosine.
Vertical shift:
Amplitude and period follow from the cosine base function.
Step-by-Step Guidance
Graph as a reference.
Draw vertical asymptotes where .
Sketch the secant curves as the reciprocal of the cosine graph, shifted down by $8$.
Try sketching the graph before checking the answer!
Q12. Graph at least two cycles of the function .
Background
Topic: Graphing Cosecant Functions
Key features:
Cosecant is the reciprocal of sine.
Period: $6\frac{2\pi}{\frac{\pi}{3}}$)
Reflection over the x-axis due to the negative sign
Step-by-Step Guidance
Graph as a reference.
Draw vertical asymptotes where the sine function is zero.
Sketch the cosecant curves as the reciprocal of the sine graph, reflected over the x-axis.