Equation reasoning
Explains equations, step by step
From kinematics to calculus — Bela breaks down every line, names the rule used, and shows the next step before it takes it.
Now on iOS
Your AI tutor for physics & math.
Snap an equation, ask out loud, or type a problem. Bela explains every step in plain language — like a patient tutor who never runs out of time.
10,000+ students learning with Bela this week
9:415G
Hi, I'm Bela
Want help with that integral?
You asked
∫ x² · cos(x) dx
Step 1
Use integration by parts: u = x², dv = cos(x) dx
Step 2
Then du = 2x dx, v = sin(x)
Step 3
= x²·sin(x) − ∫ 2x·sin(x) dx
Tap to ask another question
Features
Built like a tutor, not a calculator.
Bela doesn't just spit out answers. It walks you through the reasoning so the next problem feels easier than the last.
Voice recognition
Just ask out loud
Hands-free help. Ask "What's the derivative of x squared?" while you're drawing on paper, and Bela talks you through it.
Ask anything
A patient tutor, on demand
Type, paste, or photograph a problem. Bela checks your work, suggests where you went wrong, and asks Socratic follow-ups.
How it works
Three taps from stuck to "oh, I get it now."
Bela is built for the moments mid-homework when you don't want a textbook — you want a friend who happens to be very good at calculus.
- 01
Capture the problem
Snap a photo, paste a screenshot, type it, or just ask out loud — whatever's fastest.
- 02
Bela reasons through it
You see the rule, the substitution, the algebra — every step labelled and explained.
- 03
You stay in the loop
Ask "why?" at any line. Bela rewinds, gives a smaller example, then moves on with you.
Equation explainer
"Why does this even equal that?"
Bela reads the equation, tells you which rule applies, and shows the reasoning before the algebra — so the line above never feels like a leap.
KinematicsVectorsDerivativesIntegralsLimitsSeriesTrig
Problem
d/dx [ x² · sin(x) ]
1Identify the rule
Two functions multiplied — use the product rule: (uv)' = u'v + uv'.
2Pick u and v
Let u = x² and v = sin(x). So u' = 2x and v' = cos(x).
3Plug in
= (2x)·sin(x) + x²·cos(x).
4Done
2x·sin(x) + x²·cos(x). Want me to graph this?
βTap any step to ask "why?"
Voice mode
Hands-free help while you work.
Pencil moving, paper open, calculator out — but you still need a nudge. Just speak. Bela listens, understands the math, and answers in a calm, clear voice.
- Recognizes equations spoken naturally — "x squared plus three x".
- Switches between English and notation effortlessly.
- Reads its answers back out loud — perfect for long study sessions.
Listening…
"Hey Bela, what's the derivative of x²?"
Bela replies
"Sure — pull the exponent down and subtract one. So the derivative of x² is 2x. Want me to show the limit definition behind it?"
Subjects
From algebra homework to AP Physics.
Bela covers high school through first-year university math & physics.
P
Physics
- Kinematics & motion
- Newton's laws
- Work, energy & power
- Momentum & collisions
- Circular motion
- Gravitation
- Thermodynamics
- Waves & sound
- Optics
- Electricity & magnetism
- Modern physics
M
Math
- Algebra & functions
- Geometry & trig
- Pre-calculus
- Limits & continuity
- Derivatives
- Integrals
- Differential equations
- Linear algebra
- Probability & stats
- Discrete math
- Series & sequences
Loved by students
Quiet confidence, one problem at a time.
I used to give up on physics word problems. Bela walks through them so calmly that by the third one I didn't need help.
It's like having a TA in my pocket at 1 a.m. The voice mode is wild — I just talk through my homework.
The "ask why" button changed my life. Every line of working has a reason now.
Get BelaStop staring at the page.
Stop staring at the page.
Start understanding it.
Free to download, free to try. No more dead-ends in your homework.