展开 sqrt((a(1-cos(t))^2+(asin(t))2))

解答

展开

(a (1 - cos (t))^{2} + (a sin (t)) 2)

a - 2 a cos (t) + a cos^{2} (t) + 2 a sin (t)

求解步骤

a (1 - cos (t))^{2} + (a sin (t)) \cdot 2

去除括号:

(a) = a

= a (1 - cos (t))^{2} + a sin (t) \cdot 2

(1 - cos (t))^{2} = 1 - 2 cos (t) + cos^{2} (t)

= a (cos^{2} (t) - 2 cos (t) + 1) + 2 a sin (t)

乘开

a (1 - 2 cos (t) + cos^{2} (t)) + a sin (t) \cdot 2 : a - 2 a cos (t) + a cos^{2} (t) + a sin (t) \cdot 2

= a - 2 a cos (t) + a cos^{2} (t) + 2 a sin (t)

e x p an d 7 (12 + 2)

e x p an d (3^{\frac{3}{4}} + 3)^{2}

e x p an d \frac{( x + 1 ) ( x - 1 )}{x ^{2}}

e x p an d r^{\frac{2}{5}} (r^{\frac{3}{5}} + r^{\frac{8}{5}})

e x p an d (5 - 3) \cdot (x - 7)