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Jose Roberto Cossich G

Joined Aug 2021


Hey, my name's Jose, and I'm currently a senior. I'm about the biggest Indie music fan there is, I love 80s movies (John Hughes goat), and reading in my spare time. I enjoy math because it allows me to express myself artistically, and tutor for the mere sake of those aha moments. I've taken Multivariable Calc, Linear Algebra, Real and Complex Analysis, and I'm currently taking AP Physics C.


Aug 2021 - Present

Peer Review Team

Apr 2022 - Sep 2022

Certification Team

Jun 2022 - Dec 2023

Blog Team

Jun 2022 - May 2024

Onboarding Buddy Team

Nov 2021 - Nov 2022

Community Engagement Team

Feb 2024 - Jun 2024








Countries Reached


Learners Impacted


Sessions Hosted


Tutoring Minutes


100% Mastery
Algebra 2
100% Mastery
100% Mastery
100% Mastery
Algebra 1
100% Mastery


Celina C
Meygan P
Mikayla R
Oğuz A
Mukteshwar H
Justin D
Kareena S
Mariah O
Akshay R
Drew B

Upcoming Sessions

Multivariable Calculus and Applied Linear Algebra

    9th session

Hey everyone, it's finally here! Calculus 3 (the equivalent of the first semester of a full-year course). NOTE: REQUIRED READING OF APPROXIMATELY 25 PAGES A WEEK + WEEKLY HOMEWORK (with feedback) + 1 TEST PER UNIT (in-class and graded with feedback) Prerequisites: - Calculus 1 and 2 (the equivalent of Calc BC) CONTENT COVERED: (UNIT I) Geometry of vectors and projections 1. Vector geometry in R^n 2. Planes in R^3 3. Span, subspaces, and dimension 4. Basis and orthogonality 5. Cross Products (UNIT II) Multivariable functions and optimization 6. Multivariable functions, level sets, and contour plots 7. Partial derivatives and contour plots 8. Maxima, minima, and critical points 9. Gradients, local approximations, and gradient descent 10. Constrained optimization via Lagrange multipliers (UNIT III) Geometry and algebra of matrices 11. Linear functions, matrices, and the derivative matrix 12. Linear transformations and matrix multiplication 13. Matrix algebra 14. Multivariable Chain Rule 15. Matrix inverses and multivariable Newton’s method for zeros (UNIT IV) Further matrix algebra and linear systems 16. Linear independence and the Gram–Schmidt process 17. Matrix transpose, quadratic forms, and orthogonal matrices 18. Linear systems, column space, and null space 19. Matrix decompositions: QR-decomposition and LU-decomposition (UNIT V) Eigenvalues and second partial derivatives 20. Eigenvalues and eigenvectors 21. Applications of eigenvalues: Spectral Theorem, quadratic forms, and matrix powers 22. The Hessian and quadratic approximation 23. Application of the Hessian to local extrema 24+ (special topics - TBD)

Jose Roberto Cossich G

2 spots left!

Get a 5! - AP Calculus BC/Calc II in a Month

    8th session

I got a 5 on the AP Calculus BC exam, and you can too. Having previously taught Calculus 1 (the AB curriculum) and now seeing the staggering amount of demand for further maths, I've decided to host this intensive, yet comprehensive series on Calculus 2, including a FULL work-through of a real past exam. The first two sessions will serve as a review of differential calculus. Below are what we will cover: INTEGRATION AND APPLICATIONS (UNIT 1) 1. Introduction to accumulation of change 2. Left and right Riemann sums; over and under-approximation 3. Midpoint and trapezoidal sums 4. Definition of indefinite integral using as the limit of Riemann sums 5. The Fundamental Theorem of Calculus (including the proof), antiderivatives, and definite integrals 6. Interpretation of accumulation functions: negative definite integrals, definite integrals over a single point; graphical interpretation and evaluation. 7. Integrating sums of functions, switching the bounds of integration, and with functions as bounds. 8. The reverse power rule, u-substitution, and integration by parts 9. Antiderivatives of all the previously mentioned functions 10. Improper integrals 11. Finding the average value of a function on an interval 12. Connecting position, velocity, and acceleration functions using integrals 13. Using accumulation functions and definite integrals in applied contexts 14. Finding the area between curves expressed as functions of x 15. Finding the area between curves expressed as functions of y 16. Finding the area between curves that intersect at more than two points 17. Volumes with cross sections: squares and rectangles 18. Volumes with cross sections: triangles and semicircles 19. Volume with disc method: revolving around x- or y-axis 20. Volume with disc method: revolving around other axes 21. Volume with washer method: revolving around x- or y-axis 22. Volume with washer method: revolving around other axes 23. The arc length of a smooth, planar curve and distance traveled 24. Calculator-active practice DIFFERENTIAL EQUATIONS (UNIT 2): 1. Modeling situations with differential equations 2. Verifying solutions for differential equations 3. Sketching slope fields 4. Reasoning using slope fields 5. Approximating solutions using Euler’s method 6. Finding general solutions using separation of variables 7. Finding particular solutions using initial conditions and separation of variables 8. Exponential models with differential equations 9. Logistic models with differential equations PARAMETRIC EQUATIONS AND VECTOR-VALUED FUNCTIONS (UNIT 3): 1. Defining and differentiating parametric equations 2. Second derivatives of parametric equations 3. Finding arc lengths of curves given by parametric equations 4. Defining and differentiating vector-valued functions 5. Solving motion problems using parametric and vector-valued functions 6. Defining polar coordinates and differentiating in polar form 7. Finding the area of a polar region or the area bounded by a single polar curve 8. Finding the area of the region bounded by two polar curves 9. Calculator-active practice INFINITE SERIES (UNIT 4): 1. Defining convergent and divergent infinite series 2. Working with geometric series 3. The nth-term test for divergence 4. Integral test for convergence 5. Harmonic series and p-series 6. Comparison tests for convergence 7. Alternating series test for convergence 8. Ratio test for convergence 9. Determining absolute or conditional convergence 10. Alternating series error bound 11. Finding Taylor polynomial approximations of functions 12. Lagrange error bound 13. Radius and interval of convergence of power series 14. Finding Taylor or Maclaurin series for a function 15. Representing functions as power series

Jose Roberto Cossich G

3 spots left!

Multivariable Calculus - Integration and Vector Analysis


Are you interested in learning Calculus 3? Well, this course is the equivalent of a second-semester course, a continuation of my last series. Don't worry though if you weren't there. This series can be taken by anyone who has completed the only prerequisite: Calculus 1 (with integration) and the rest of the necessary background information will be covered or reviewed in the initial sessions. NOTE: Required reading of about 15 pages a week + weekly homework (with feedback) + 1 test per unit (in-class and graded with feedback) Sessions are between 1h15m to 1h30m. Content Covered: (UNIT I) Single-Variable Integration and Applications 1. Physical interpretations of the integral and the average value of a function over an interval 2. Finding the area between curves expressed as functions of y 3. Finding the area between curves that intersect at more than two points 4. Volumes with cross sections: squares, rectangles, triangles, and semicircles 5. Volume with the disc and washer method: revolving around x-, y-, and different axes 6. Arc length, distance traveled, and unit calculator practice (UNIT II) Multivariable Integration and Applications 7. Formulating Riemann sums 8. The Double Integral and Iterated Integral 9. Applications of The Double Integral 10. Triple Integrals 11. The Jacobian and uv-substitution 12. Integration in Polar, Cylindrical, and Spherical Coordinates 13. Applications of Triple Integrals (Unit III) Single-Variable Vector Analysis 14. Defining and differentiating parametric vector-valued functions 15. Finding arc lengths of curves given by parametric equations and solving motion problems 16. Defining polar coordinates and differentiating in polar form 17. Finding the area of a polar region bounded by one and multiple polar curves, and unit calculator practice. (Unit IV) Multivariable Vector Analysis 18. Scalar-valued Line Integrals 19. Vector-valued line integrals 20. Path Independence 21. Exact Differentials 22. Divergence and Green's Theorem 23 Curl, Stokes' Theorem, and parameterizing surfaces. 24. Flux and Divergence Theorem 25+ (applications to Electrodynamics and other special topics?)

Jose Roberto Cossich G


Featured Feedback


Thank you for this session! I really like the practice problems which helps reinforce the concepts that we have already learned! I also really appreciate how you are attentive to each learner's needs :)

Learner · 2 days ago

Bravo! Schoolhouse MUN 2024 was a fantastic event! Each delegate was super respectful of one another, discussions were lively, and the chairs kept things on track. The opening and closing ceremonies were excellent and very fun too! I am looking forward to next year's Schoolhouse MUN. Thank you all for all of your hard work!

Learner · 6 mo. ago

Thank you so much! I'm so excited for the rest of this course, and thank you for starting it! I'm so happy that Schoolhouse has a Linear Algebra series now :) can't wait for future sessions, and have a great day/night!

Learner · 5 mo. ago

I want to express my gratitude for this Model United Nations conference. I thoroughly enjoyed the experience of interacting with all the participants. The debates and discussions were thought-provoking, and I gained a lot of knowledge and insights on various global issues. It was an incredible opportunity to engage with intelligent and motivated individuals who share similar interests and passions. Overall, the conference was an excellent platform to develop my diplomacy skills, and I had a lot of fun participating in it.

Learner · 6 mo. ago


  • Peer Review Team

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