把抛物线y=-3(x-1)^2向上平移k个单位,所得抛物线与x轴交于点A(m,0),点B(n,0),若m^2+n^2=26/9,请求出k的值
y=-3(x-1)^2+k
y=-3x^2+6x-3+k
m^2+n^2=26/9
(m+n)^2-2mn=26/9
根据韦达定理
4+1-k/3=26/9
19/9=k/3
k=19/3
把抛物线y=-3(x-1)^2向上平移k个单位,所得抛物线与x轴交于点A(m,0),点B(n,0),若m^2+n^2=26/9,请求出k的值
y=-3(x-1)^2+k
y=-3x^2+6x-3+k
m^2+n^2=26/9
(m+n)^2-2mn=26/9
根据韦达定理
4+1-k/3=26/9
19/9=k/3
k=19/3