Question 951509
Show the steps on how to prove of the following identity:
tan (a + B) = tan a + tan B/ 1- tan a tan B
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{{{tan(a+b)=sin(a+b)/cos(a+b)=(sinacosb+cosasinb)/(cosacosb-sinasinb)}}}
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divide each term by cosacosb
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{{{((sinacosb)/(cosacosb)+(cosasinb)/(cosacosb))/((cosacosb)/(cosacosb)-(sinasinb)/(cosacosb))}}}
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{{{((sina)/(cosa)+(sinb)/(cosb))/(1-(sinasinb)/(cosacosb))}}}
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{{{(tana+tanb)/(1-tanatanb)}}}