Question

X (pangkat) 2-5x-7=0 nilai dari 1/α(pangkat) 2+1/β(pangkat) 2 adalah

Answer 1

X" - 5x -7 =0
ditanya
1/A" + 1/B"?

Dijawab
A + B = -b/a = -(-5)/1 =5

A.B = c/a = -7/1 = -7

1/A" + 1/B" = (A" + B")/ (AB)"

= ((A+B)" -2AB)/ AB"

=( 5" - 2(-7)) / (-7)"

= (25 +14) / 49

= 39 /49