निम्नं समाकलनों को मान ज्ञात कीजिये। - ( पाठयपुस्तक उदाहरण 13 )
(i) `I = int cos3x cos4x dx`
(ii) `intsin^(2) xdx`
(iii) `intcos^(3) xdx`
(iv) `intsin^(4) xdx`

Answer

(i) ` = (1)/(14) sin 7 x +(1)/(2) sin x +c`
(ii) ` therefore I = (1)/(2)[ x - (sin 2 x)/(2) +c]`
(iii) ` = (1)/(4) [ (sin 3x)/(3) + 3 sin x] +c`
(iv) ` = (1)/(8) [ 3x + (sin 4x )/(4)-2 sin 2x] +c`