Lesson Library + Practice Sets
The full 175-lesson Library and all 46 Practice Sets, marked instantly.
₱499one payment
UPCAT Math Review · Functions
Inverse Functions: The Function That Undoes the Function
Find f⁻¹(x) for f(x) = (x + 2)/3 step by step. Rewrite f(x) as y, swap x and y, solve for y and rename — then see the two graphs mirrored in the line y = x.
This lesson is part of a NEXUS plan.
Log in if you already have a plan, or pick one below. You pay once with any QR Ph app (GCash, Maya, your bank) and the whole library unlocks straight away.
Plans
Pick a plan, pay once by QR Ph
The diagnostic exam stays free. Everything else is one payment, no subscription.
All-Access Pass
A seat in a UPCAT 2028 Live Class, plus the Lesson Library and every Practice Set.
₱2,500early bird until Dec 9, 2026 · ₱3,000 after