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Three simple steps: (1) Share an assignment from thousands of standards-aligned topics using a share code. (2) Students speak and draw their thinking naturally, and Goblins responds with Socratic questioning that sounds just like their teacher. (3) Teachers get real-time formative insights showing what students struggle with and suggestions to inform instruction.

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Can I use my own voice with Goblins?

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What math levels does Goblins cover?

Goblins covers math from Grade 5 through AP Calculus, including thousands of standards-aligned topics. Teachers can also upload their own content for custom assignments at any level.

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Does Goblins support English Language Learners?

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What grade level is M.4HSTP taught?

This standard is part of the M curriculum in West Virginia College- and Career-Readiness Standards for Mathematics.

High School Mathematics IV – Trigonometry/Pre-calculus Math Standards | West Virginia | West Virginia College- and Career-Readiness Standards for Mathematics

High School Mathematics IV – Trigonometry/Pre-calculus

High School Mathematics IV: Trigonometry/Pre-calculus focuses on advanced function families and their applications. Complex numbers, matrices as transformations, trigonometric functions and their identities, and probability distributions including expected value form the core content. Series notation, infinite geometric series, and mathematical induction extend students into the formal reasoning of calculus and discrete mathematics.

M.4HSTP.1Find the conjugate of a complex number; use conjugates to find moduli (magnitude) and quotients of complex numbers.M.4HSTP.10Use matrices to represent and manipulate data (e.g., to represent payoffs or incidence relationships in a network).M.4HSTP.11Multiply matrices by scalars to produce new matrices (e.g., as when all of the payoffs in a game are doubled.M.4HSTP.12Add, subtract and multiply matrices of appropriate dimensions.M.4HSTP.13Understand that, unlike multiplication of numbers, matrix multiplication for square matrices is not a commutative operation, but still satisfies the associative and distributive properties.M.4HSTP.14Understand that the zero and identity matrices play a role in matrix addition and multiplication similar to the role of 0 and 1 in the real numbers. The determinant of a square matrix is nonzero if and only if the matrix has a multiplicative inverse.M.4HSTP.15Multiply a vector (regarded as a matrix with one column) by a matrix of suitable dimensions to produce another vector. Work with matrices as transformations of vectors.M.4HSTP.16Work with 2 × 2 matrices as transformations of the plane and interpret the absolute value of the determinant in terms of area.M.4HSTP.17Represent a system of linear equations as a single matrix equation in a vector variable.M.4HSTP.18Find the inverse of a matrix if it exists and use it to solve systems of linear equations (using technology for matrices of dimension 3 × 3 or greater).M.4HSTP.19Graph functions expressed symbolically and show key features of the graph, by hand in simple cases and using technology for more complicated cases. Graph rational functions, identifying zeros and asymptotes when suitable factorizations are available, and showing end behavior.M.4HSTP.2Represent complex numbers on the complex plane in rectangular and polar form (including real and imaginary numbers), and explain why the rectangular and polar forms of a given complex number represent the same number.M.4HSTP.20Write a function that describes a relationship between two quantities, including composition of functions. For example, if T(y) is the temperature in the atmosphere as a function of height, and h(t) is the height of a weather balloon as a function of time, then T(h(t)) is the temperature at the location of the weather balloon as a function of time.M.4HSTP.21Find inverse functions.M.4HSTP.22Understand the inverse relationship between exponents and logarithms and use this relationship to solve problems involving logarithms and exponents.M.4HSTP.23Use special triangles to determine geometrically the values of sine, cosine, tangent for π/3, π/4 and π/6, and use the unit circle to express the values of sine, cosine, and tangent for π–x, π+x, and 2π–x in terms of their values for x, where x is any real number.M.4HSTP.24Use the unit circle to explain symmetry (odd and even) and periodicity of trigonometric functions.M.4HSTP.25Understand that restricting a trigonometric function to a domain on which it is always increasing or always decreasing allows its inverse to be constructed.M.4HSTP.26Use inverse functions to solve trigonometric equations that arise in modeling contexts; evaluate the solutions using technology, and interpret them in terms of the context.M.4HSTP.27Solve more general trigonometric equations. (e.g., 2 sin^2x + sin x - 1 = 0 can be solved using factoring.M.4HSTP.28Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.M.4HSTP.29Graph trigonometric functions showing key features, including phase shift.M.4HSTP.3Represent addition, subtraction, multiplication and conjugation of complex numbers geometrically on the complex plane; use properties of this representation for computation. (e.g., (–1 + √3 i)^3 = 8 because (–1 + √3 i) has modulus 2 and argument 120°.M.4HSTP.30Derive the equations of ellipses and hyperbolas given the foci, using the fact that the sum or difference of distances from the foci is constant.M.4HSTP.31Give an informal argument using Cavalieri’s principle for the formulas for the volume of a sphere and other solid figures.M.4HSTP.32Define a random variable for a quantity of interest by assigning a numerical value to each event in a sample space; graph the corresponding probability distribution using the same graphical displays as for data distributions.M.4HSTP.33Calculate the expected value of a random variable; interpret it as the mean of the probability distribution.M.4HSTP.34Develop a probability distribution for a random variable defined for a sample space in which theoretical probabilities can be calculated; find the expected value. (e.g., Find the theoretical probability distribution for the number of correct answers obtained by guessing on all five questions of a multiple-choice test where each question has four choices, and find the expected grade under various grading schemes.)M.4HSTP.35Develop a probability distribution for a random variable defined for a sample space in which probabilities are assigned empirically; find the expected value. For example, find a current data distribution on the number of TV sets per household in the United States, and calculate the expected number of sets per household. How many TV sets would you expect to find in 100 randomly selected households?M.4HSTP.36Weigh the possible outcomes of a decision by assigning probabilities to payoff values and finding expected values.M.4HSTP.37Develop sigma notation and use it to write series in equivalent form. For example, write [n∑i=1](3i^2 + 7) as [3n∑i=1]i^2 + 7[n∑i=1]1.M.4HSTP.38Apply the method of mathematical induction to prove summation formulas. For example, verify that [n∑i=1]i^2 = (n(n+1)(2n+1))/6.M.4HSTP.39Develop intuitively that the sum of an infinite series of positive numbers can converge and derive the formula for the sum of an infinite geometric series.M.4HSTP.4Calculate the distance between numbers in the complex plane as the modulus of the difference and the midpoint of a segment as the average of the numbers at its endpoints.M.4HSTP.40Apply infinite geometric series models. For example, find the area bounded by a Koch curve.M.4HSTP.5Recognize vector quantities as having both magnitude and direction. Represent vector quantities by directed line segments and use appropriate symbols for vectors and their magnitudes (e.g., v, |v|, ||v||, v).M.4HSTP.6Find the components of a vector by subtracting the coordinates of an initial point from the coordinates of a terminal point.M.4HSTP.7Solve problems involving velocity and other quantities that can be represented by vectors.M.4HSTP.8Add and subtract vectors.M.4HSTP.9Multiply a vector by a scalar.M.4HSTP.ASFAnalysis and Synthesis of Functions M.4HSTP.BRBuilding Relationships among Complex Numbers, Vectors, and Matrices M.4HSTP.DAGDerivations in Analytic Geometry M.4HSTP.MPModeling with Probability M.4HSTP.SILSeries and Informal Limits M.4HSTP.TITTrigonometric and Inverse Trigonometric Functions of Real Numbers

Example Problems

Divide the following complex numbers.

\frac{5 + 5i}{1 + 2i}

The image files captured by a drone have a mean size of

2.8 \text{ megabytes}

with a standard deviation of

0.6 \text{ megabytes}

.

What will be the mean of the distribution of file sizes in kilobytes?

1 \text{ megabyte}

equals

1024 \text{ kilobytes}

The component form of vector

\vec{v}

\vec{v} = (2, 0)

.
Find

5\vec{v}

Solve the following system of equations:

\begin{cases} x + y + z = 2 \\ y - 3z = 1 \\ 2x + y + 5z = 0 \end{cases}

Consider the following rational function f.

f(x) = \frac{-2x^6 + x^2}{4x^2 - 9}

Determine f's end behavior.

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M.4HSTP: High School Mathematics IV – Trigonometry/Pre-calculus

High School Mathematics IV – Trigonometry/Pre-calculus