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BiologyCell Biology

What Are the Monomers of Lipids?

Learn why glycerol and fatty acids are the building components of fats, while lipids have no universal repeating monomer.

BiologyCell Biology

How Many ATP Are Produced in Glycolysis? Total vs. Net

Glycolysis produces 4 ATP per glucose in total and gains 2 ATP net after its investment. See the accounting and pathway boundary.

BiologyGenetics

Where Does Transcription Take Place in a Eukaryotic Cell?

The nucleus is the expected answer for nuclear genes, but mitochondria and chloroplasts also transcribe their own DNA.

MathCalculus

Integral Test for Convergence: Does ∑ n/(3n² + 1) Converge?

The positive decreasing extension has a divergent logarithmic improper integral, so ∑ n/(3n² + 1) diverges by the integral test.

MathCalculus

Shell Method Formula: Volume of y = 3x − x² About the y-Axis

Using shells of radius x and height 3x − x² gives V = 2π∫₀²x(3x − x²) dx = 8π cubic units.

MathCalculus

Derivative of Trigonometric Functions: Differentiate csc x + x tan x

The sum and product rules give f′(x) = −csc x cot x + tan x + x sec²x on the original function's domain.

MathCalculus

What Is the Mean Value Theorem? Apply It to a Falling Rock

The rock hits after 5/2 s, its average velocity is −40 ft/s, and the Mean Value Theorem identifies c = 5/4 s when instantaneous velocity matches it.

PhysicsClassical Physics

Elastic vs Inelastic Collision: Which Cases Conserve Kinetic Energy?

The first record is perfectly inelastic because the objects stick and kinetic energy falls from 27 J to 24 J. Records 2 and 3 conserve both momentum and kinetic energy, so they are perfectly elastic.

PhysicsClassical Physics

How to Find Tension in a Two-Mass Atwood Machine

For ideal masses of 2.00 kg and 4.00 kg, the heavier mass accelerates downward at 3.27 m/s², the lighter mass accelerates upward at the same rate, and the string tension is 26.1 N.