lim(x→0)tan(2x^2)/1-cosx求解要過程

lim(x→0)tan(2x^2)/1-cosx求解要過程


lim(x→0)tan(2x^2)/1-cosx
=lim(x→0)tan(2x^2)/2sin²;x/2
=4lim(x→0)[tan(2x^2)/2x²;][(x/2)²;/(2sin²;x/2)]
=4



已知|3x+y-2|+(2x+3y+1)^2=0,求的x,y值.


您好!
由題得|3x+y-2|=0,(2x+3y+1)^2=0
故3x+y-2=0
2x+3y+1=0
解得x=1
y=-1
謝謝~~



解方乘:(1)5(X—8)=3X(2)9(2X—3)—2=5(2X—1)
(急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.急用.


1.5(X-8)=3X
所以:5X-40=3X
所以:5X-3X=40
所以:2X=40
所以:X=20
2.9(2X-3)-2=5(2X-1)
所以:18X-27-2=10X-5
所以:18X-10X=-5+27+2
所以:8X=24
所以:X=3