Letr(t)=x(t),y(t),z(t).Provideadefinitionforthecontinuityofthevectorfunctionratapointcinthedomainofr.

Short Answer

Expert verified

r(t)=cost,sint,tantisacontinuousvectorfunctionatπ4whichisinthedomainofr(t).

Step by step solution

01

Step 1. Given information

r(t)=x(t),y(t),z(t)

02

Step 2. Result

Thefunctionrissaidtobecontinuousatapointcinthedomainofriflimtcr(t)=r(c).Thatis,limtcx(t),y(t),z(t)=limtcx(t)i+limtcy(t)j+limtcz(t)k=x(c)i+y(c)j+z(c)kForexample:letr(t)=cost,sint,tantandletc=π4isinthedomainofr(t).Thenlimtcr(t)=limtπ4cost,sint,tant=limtπ4costi+limtπ4sintj+limtπ4tantk=cosπ4i+sinπ4j+tanπ4k=12i+12j+1(k)=22i+22j+kThusr(t)=cost,sint,tantisacontinuousvectorfunctionatπ4whichisinthedomainofr(t).

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