IB›IB Maths: Analysis and Approaches HL›Mind maps1.1 Scientific notationIB Maths: Analysis and Approaches HL: Mind mapStudy pack PDFAlso for this subtopic:Revision notesFlashcardsSubtopic testCover factsWhat is it?Written as a×10ka\times10^{k}a×10k with 1≤a<101\le a<101≤a<10k is an integer exponentLarge numbers → positive exponentNumbers below 1 → negative exponentMultiply, divideMultiply front numbers, add exponentsDivide front numbers, subtract exponentsThen adjust so front number is 1 to 10(8×10−6)(2.5×1013)=2×108(8\times10^{-6})(2.5\times10^{13}) = 2\times10^{8}(8×10−6)(2.5×1013)=2×108Scientific notationstandard forma×10ka\times10^{k}a×10kAdd, subtractNeed the same power of 10 first4.5×1012−0.15×10124.5\times10^{12} - 0.15\times10^{12}4.5×1012−0.15×1012Then combine the front numbersMuch smaller number barely changes the answerAccuracyGive 3 s.f. unless told otherwiseSig figs are the digits of aRound in context, e.g. whole daysEstimate first as a sense checkExam tipsNever write calculator notation 5.2E3012×10512\times10^{5}12×105 is not standard formFront number ×10 → exponent goes down 1Do not add exponents when adding numbers