Lösung 4.3:8a
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
K (Lösning 4.3:8a moved to Solution 4.3:8a: Robot: moved page) |
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- | {{ | + | We rewrite |
+ | <math>\text{tan }v</math> | ||
+ | on the left-hand side as | ||
+ | <math>\frac{\sin v}{\cos v}</math>, so that | ||
+ | |||
+ | |||
+ | <math>\tan ^{2}v=\frac{\sin ^{2}v}{\cos ^{2}v}</math> | ||
+ | |||
+ | |||
+ | If we then use the Pythagorean identity | ||
+ | |||
+ | |||
+ | <math>\cos ^{2}v+\sin ^{2}v=1</math> | ||
+ | |||
+ | |||
+ | and rewrite | ||
+ | <math>\text{cos}^{\text{2}}v</math> | ||
+ | in the denominator as | ||
+ | <math>\text{1}-\text{sin}^{\text{2}}v\text{ }</math>, we get what we are looking for on the right-hand side. The whole calculation is | ||
+ | |||
+ | |||
+ | <math>\tan ^{2}v=\frac{\sin ^{2}v}{\cos ^{2}v}=\frac{\sin ^{2}v}{1-\sin ^{2}v}</math> |
Version vom 10:37, 30. Sep. 2008
We rewrite
\displaystyle \text{tan }v
on the left-hand side as
\displaystyle \frac{\sin v}{\cos v}, so that
\displaystyle \tan ^{2}v=\frac{\sin ^{2}v}{\cos ^{2}v}
If we then use the Pythagorean identity
\displaystyle \cos ^{2}v+\sin ^{2}v=1
and rewrite
\displaystyle \text{cos}^{\text{2}}v
in the denominator as
\displaystyle \text{1}-\text{sin}^{\text{2}}v\text{ }, we get what we are looking for on the right-hand side. The whole calculation is
\displaystyle \tan ^{2}v=\frac{\sin ^{2}v}{\cos ^{2}v}=\frac{\sin ^{2}v}{1-\sin ^{2}v}