please i need help with this problem.

cosB/1-tanB + sinB/1-cotB = sinB + cosB

how can i prove this identity?

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- Nov 28th 2009, 11:37 AMCooksproving identities
please i need help with this problem.

cosB/1-tanB + sinB/1-cotB = sinB + cosB

how can i prove this identity? - Nov 28th 2009, 01:13 PMskeeter
working on the left side ...

$\displaystyle \frac{\cos{\beta}}{\cos{\beta}} \cdot \frac{\cos{\beta}}{1-\tan{\beta}} + \frac{\sin{\beta}}{\sin{\beta}} \cdot \frac{\sin{\beta}}{1-\cot{\beta}}$

$\displaystyle \frac{\cos^2{\beta}}{\cos{\beta} - \sin{\beta}} + \frac{\sin^2{\beta}}{\sin{\beta}-\cos{\beta}}$

$\displaystyle \frac{\cos^2{\beta}}{\cos{\beta} - \sin{\beta}} - \frac{\sin^2{\beta}}{\cos{\beta} - \sin{\beta}}$

$\displaystyle \frac{\cos^2{\beta}-\sin^2{\beta}}{\cos{\beta} - \sin{\beta}}$

factor the numerator and finish it up ... - Dec 1st 2009, 02:12 AMmrmohamed
**hi all**