(2angle(pi)/(12))^3=8angle(pi)/(4).

在 Delta ABC 中, angle A=dfrac (pi )(6),在 Delta ABC 中, angle A=dfrac (pi )(6),

17.-|||-如图, Delta AOD 与 Delta BOC 存在对顶角 angle AOD=angle BOC=dfrac (pi )(4) ,AC=2

(B) pi +dfrac (4)(3) (C) pi +2 . (D) pi +dfrac (8)(3)

sqrt (2)pi :2 C. sqrt (2)pi :4 D. sqrt (2)pi :8

(4)int_((pi)/(4))^(pi)/(3)(x)/(sin^2)xdx;(4)$\int_{\frac{\pi}{4}}^{\frac{\pi}{3}

下列复数① sqrt[4](6)(cos (pi)/(8)+i sin (pi)/(8));② sqrt[4](6)(cos (pi)/(8)-i sin (p

sqrt (2)pi -|||-C. dfrac (sqrt {2pi )}(4)-|||-D. dfrac (sqrt {2pi )}(8)

当AP与-|||-div 0 相切时,点B恰好落在 div 0 上,如图(2).-|||-请仅就图(2)的情形解答下列问题.-|||-(1)求证: angle

2.已知:如图,在 Delta ABC 中, angle BAE=angle CAE angle ADC=(90)^circ angle B=(40)^cir

设 M=int_(-(pi)/(2))^(pi)/(2) (sin x)/(1+x^2) cos^4 x dx，N=int_(-(pi)/(2))^(pi)/(