You want to MOVE the (implied) decimal point to the left until its placement indicates a number greater than or equal to 1 and less than 10; and then indicate the power of ten which would reverse that decimal placement.
3.42______ happens if you move decimal point 6 places.
This means your power of ten must be .
Your number converted to scientific notation is .
Please ignore the dots around the x; rendering was not working and so they were necessary for the expression to appear.
That does show the use of "x" as a multiplication symbol.
(