MathLab with Mr. Ahmed
MathLab with Mr. Ahmed is a math learning website by Ahmed Amasha, a mathematics teacher teaching the American curriculum. Explore Algebra 2, Precalculus, Calculus, and SAT and PSAT Math Prep through lessons, focused practice and printable resources.
Before you solve
Ideas in this lesson
Idea 1 of 3
Hyperbolic derivatives
The derivative of sinh is cosh; the derivative of cosh is sinh. Unlike cos,cosh introduces no negative sign.
Worked example 1
Find f′(0) for f(x)=sinh(2x). - f′(x)=2cosh(2x)
- cosh0=1; sinh0=0; sech 0=1
- f′(0)=2
Answer: 2
Worked example 2
Find f′(0) for f(x)=cosh(3x). - f′(x)=3sinh(3x)
- cosh0=1; sinh0=0; sech 0=1
- f′(0)=0
Answer: 0
Idea 2 of 3
Hyperbolic integration
Reverse the derivative formulas and account for any inner chain-rule factor.
Worked example 1
Evaluate ∫012coshxdx. - F(x)=2sinhx
- F(1)−F(0)=2sinh(1)≈2.35
Answer: 2sinh(1)≈2.35
Worked example 2
Evaluate ∫013sinhxdx. - F(x)=3coshx
- F(1)−F(0)=3(cosh(1)−1)≈1.63
Answer: 3(cosh(1)−1)≈1.63
Idea 3 of 3
The hyperbolic tangent
The derivative of tanh is sech 2. Its value at zero follows from cosh0=1.
Worked example 1
Find f′(0) for f(x)=sinh(2x). - f′(x)=2cosh(2x)
- cosh0=1; sinh0=0; sech 0=1
- f′(0)=2
Answer: 2
Worked example 2
Find f′(0) for f(x)=cosh(3x). - f′(x)=3sinh(3x)
- cosh0=1; sinh0=0; sech 0=1
- f′(0)=0
Answer: 0
Resource alignment: Larson & Edwards, Calculus of a Single Variable, Tenth Edition, §5.8,p. 383. Explanations, diagrams and numerical practice variants are original MathLab content aligned to this section.