Вопрос
ct all expressions matching the value of indefinite Iral int tan(t)/(2)dt 2cos^2t+C (2)/(cos^2)(t)/(2)+C -2ln(cos(t)/(2))+c -ln(cos(t)/(2))+c
Решения
4.2
(256 Голоса)
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Экспертная проверка
элита · Репетитор 8 лет
Ответ
The correct answer is:
Explanation:The integral
can be solved using the substitution method. Let
, then
, and
. Substituting these into the integral, we get:
Now, we can use the identity
and integrate:
Using the integral of secant, we have:
Substituting back
, we get:
Now, we can use the identity
and simplify:
\tan u = \frac{\sin u}{\cos u}
2\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}| + C
\sin^2 u + \cos^2 u = 1
2\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}| + C = 2\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}| + C
\ln|a| = \ln|b| + \ln|c|
2\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}| + C = 2\ln|1 + \sin\frac {t}{2}| - 2\ln|\cos\frac {t}{2}| + C
\ln|a| - \ln|b| = \ln|\frac{a}{b}|
2\ln|1 + \sin\frac {t}{2}| - 2\ln|\cos\frac {t}{2}| + C = 2\ln|\frac{1 + \sin\frac {t}{2}} {t}{2}}| + C
\ln|a| + C = \ln|a| + C
2\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}| + C = \ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}|^2 + C
\ln|a|^2 = \ln|a^2|
\ln|\frac{1 + \sin\frac {t}{2}}{\cos\frac {t}{2}}|^2 + C =|\frac{(1 + \sin\frac {t}{2})^2}{\cos^2\frac {t}{2}}| + C
\ln|a| + C = \ln|a| + C
\ln|\frac{(1 + \sin\frac {t}{2})^2}{\cos^2\frac {t}{2}}| + C = \ln|\frac{(1 + \sin\frac {t}{2})^2}{\cos^2\frac {t}{2}}| + C
\ln|a| + C = \ln|a| + C
\ln|\frac{(1 +\t}{2})^2}{\cos^2\frac {t}{2}}| + C = \ln|\frac{(1 + \sin\frac {t}{2})^2}{\cos^2\frac {t}{2}}| +