bless up
It's not correct because if t is odd, your result will be an odd number.
>>131682
thank you. also what if there was a number that 12.04378 It asked to round to 3sf and I wrote 12 but the mark scheme wrote 12.0, would I still be correct?
doesn't seem right.
for t=1 the expression yields 9. the doubling only applies to the first term.
for even numbers it's clearly never a prime
the t^2 gets multiplied by 2, 5 times an even number is always an even number and the plus 2 is also even, so the end result will always be an even number and never a prime
so you'd need to figure out why odd numbers cannot yield prime numbers
>>131685
this is what the mark scheme says
>>131683
No.
The sig fig system is designed to communicate the precision of your measurements in short hand. "12" is interpreted roughly as "a measured value doubtful in the ones place: as low as 11 and as high as 13" while "12.0" is interpreted roughly as "a measured value doubtful in the tenths place: as low as 12.9 and as high as 13.1".
>>131685
The actual solution (as I assume OP was given?) is to factor 2t^2+5t+2 yeilding (2t+1)(t+2). Since both 2t+1 and t+2 will be whole numbers for any whole t>0 the complete expression necessarily has at least 2 factors.
