Evaluate the limit (y-->3) [sqrt(y^2+5y+1) - sqrt(y^2+3y+7)] / [y-3]
step by step please, i am lost.
step by step please, i am lost.
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[sqrt(y^2+5y+1) - sqrt(y^2+3y+7)] / [y-3]
Multiply [sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
to both the num. and den.
Recall (a+b)(a-b) = a^2-b^2
The num
= (y^2+5y+1) - (y^2+3y+7)
= 2y - 6
[sqrt(y^2+5y+1) - sqrt(y^2+3y+7)] / [y-3]
= (2y-6) / (y-3)[sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
= 2/ [sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
Take y to 3.
2/(sqrt25 + sqrt25)
= 2/10
=1/5
Multiply [sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
to both the num. and den.
Recall (a+b)(a-b) = a^2-b^2
The num
= (y^2+5y+1) - (y^2+3y+7)
= 2y - 6
[sqrt(y^2+5y+1) - sqrt(y^2+3y+7)] / [y-3]
= (2y-6) / (y-3)[sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
= 2/ [sqrt(y^2+5y+1) + sqrt(y^2+3y+7)]
Take y to 3.
2/(sqrt25 + sqrt25)
= 2/10
=1/5
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The limit does not exist....