Q. Find the values of x and y in the following scalar multiplication.7⋅⎣⎡1x5⎦⎤=⎣⎡7−21y⎦⎤x=□y=□
Understanding scalar multiplication: Understand the scalar multiplication of a vector by a number. Scalar multiplication involves multiplying each component of the vector by the scalar (in this case, 7).
Multiplying the first component: Multiply the first component of the vector by the scalar. 7×1=7This matches the first component of the resulting vector, confirming that the scalar multiplication for this component is correct.
Setting up the equation for the second component: Set up the equation for the second component of the vector after scalar multiplication.7×x=−21Now we need to solve for x.
Solving for x: Solve for x.x=7−21x=−3This gives us the value of x in the scalar multiplication.
Multiplying the third component: Multiply the third component of the vector by the scalar. 7×5=35This should be the value of y in the resulting vector.
Verifying the calculated values: Verify that the calculated values satisfy the original scalar multiplication equation.7×[1,x,5]=[7,−21,y]Substitute x=−3 and y=35 into the equation:7×[1,−3,5]=[7,−21,35]This matches the given resulting vector [7,−21,y].