Vector Arithmetic — Question 3

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Question 3

For what value of tt are ⟨t+1,2t−3,5⟩\langle t+1,2t-3,5\rangle and ⟨4,3,5⟩\langle4,3,5\rangle equal? If none exists, identify the obstruction.

Original worksheet page 1: question and worked solution for 5-2-003
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Question 3 – Solution

Write every vector in matching component order. Perform scalar multiplication before addition or subtraction, then interpret the resulting components in the context of the problem.

See the diagram in the original worksheet below.

Equal vectors require equality of every component.

The first component gives t+1=4t+1=4, so t=3t=3; the second gives 2t−3=32t-3=3, also t=3t=3.

The third components already agree, so the unique value is t=3\boxed{t=3}.

The result follows from the defining vector formulas used above, and each component, magnitude, or scalar condition has been checked against the information in the question.

Vector equations behave like ordinary algebra provided that every operation is performed component by component. A final component check is often the fastest verification.

Original worksheet page 2: question and worked solution for 5-2-003

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