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Derive Law of Cosines using Pythagorean Theorem

Consider the triangle ABC. Denote h the altitude through B and D the point where h intersects the (extended) base AC
Cosine function for triangle ADB.

cos α= x/c => x=c*cos α

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Answered by Jan M. • Maths tutor

3653 Views

Compare how the authors of two texts you have studied present barriers to love.

There is never a set answer for english literature. Depending on the aspects of Literature and the texts the student feels most comfortable and most competent working with, we might discuss rhythm, rhyme,...

Answered by Katy M. • English Literature tutor

8369 Views

Steel has a density of 8030kg/m^3. Show that a steel ball with a diameter of 5cm weighs approximately 5N

Using Weight = mass*gravitational strength

Using: Mass = density * volume

Using Volume = (4/3)pir³

Radius = 2.5cm = 0.025m

Volume = (4/3)pi0.025

Answered by Sameh H. • Physics tutor

13036 Views

Given that Sin(A) = 1/sqrt(3), show that Tan(A) = 1/sqrt(2)

Using: Tan(x) = Sin(x)/Cos(x)

Using: Cos(x) = sqrt(1-Sin²(x))

Cos(A) = sqrt(1-Sin²(A)) = sqrt(1-1/3) = sqrt(2)/sqrt(3)

Therefore: Tan(A) = Sin(A)/Cos(A) = (1/sqr...

Answered by Sameh H. • Maths tutor

4418 Views

What is the "chain rule"?

The "chain rule" is a handy little tool that we can use to find the derivative of a complicated function. Specifically, we use the chain rule when we have functions within functions. But what ...

Answered by Joe F. • Maths tutor

4092 Views