if the graph of y=2(x-1)^2 +k passes through the point (2.8 )
the y intercept is
ans10
give me the step PLZ
if (x )=4x^2 +2x-1 for what values of x is f(x) =-f(-x)
ans 1/2 Or -1/2
if the mini value of x^2-2x+k+2 is -2 then k =-3
write the step for me ,quick !
maths ~~~~~~~~~~~~~~helpppp
2008-11-06 6:23 am
回答 (1)
2008-11-10 6:46 am
✔ 最佳答案
y=2(x-1)2 +k passes through the point (2.8 ),∴8=2(2-1)2+k
k=6
y=2(x-1)2 +6
y=2x2-4x+2+6
=2x2-4x+8
∴ y intercept is 8.
f(x)=f(-x)
4x2 +2x-1=-[4(-x)2+2(-x)-1]
4x2+2x-1=-[4x2-2x-1]
8x2=2
x2=2/8
x2=1/4
x=1/2 or x=-1/2
x2-2x+k+2=(x2-2x+1)+k+1
=(x-1)2+k+1
∴The mini value =k+1
i.e. -2=k+1
k=-3
收錄日期: 2021-04-23 20:35:56
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