∵1
∵椭圆方程为x245+y220=1,
∵x=45+1=4(5+1)(5+1)(5-1)=
∵a=(1,1),a+2b=λa(λ>0),
∵ n(n+1)(n+2)(n+3)+1 等于?
∵直线 x=2-12ty=-1+12t(t为参数)∴
∵物体浸没在水中,∴v排=v=1×10-3m3
1,①∵ EF=ED,点F是BD的中点(已知)
: ∵an+2snsn-1=0(n≥2),
∵a+1a-1=3+22,两边同乘以a-1,得a+1=(3+22
∵sin^(-1) x=(sinx)^(-1) 又sin^(-1) x=arcsin x ∴arcsinx=1/(sin
∵A(1,2),B(2,-1),C(2,2),∴AB=(1,-3),BC=(
看图填空:(1)看图1,完成证明:∵∠A+∠D=180°(已知)∴______∥______∴∠1=______∵∠1=