Stanford University Admission Interview Tricks | No Calculator Allowed

Stanford University Admission Interview Tricks | No Calculator Allowed #exponents #matholympiad #exponentialequation

[@druariel]

What does it tell you about your methods when everyone in the comments tells you to factor out a power of 10 before anything else? How can you suggest this long process when it’s much simpler to do that and just do the whole thing in your head? 10^8(9^4-6^4) 10^8((81+36)(81-36)) 10^8(117•45) Then 10^8(you can do this multiplication several ways, including just working it out on paper, but for doing it in your head here’s one way 117•40=4680(1170 doubled twice)+117•5=585(multiplied by 10, then halved)=5265) =5265•10^8

[@juergenilse3259]

900^4-600^4= 100^4*(9^4-6^4)= (10^2)^4*((9^2)^2-(6^2)^2)= 10^8*(81^2-36^2)=h 10^8*(81-36)*(81+36)= 10^8*(45*117) 10^8*(40*117+5*117)= 10^8*(4680+585= 5265*10^8= 526500000000 Why do you not take out the common factor 100^4(=10^8) out of the difference to reduce the problem to 10^8*(81^2-36^2)?

[@eknathraykar3572]

A simpler solution --- 10^8 can be a common factor. Now work out 9^4 -6^4. 9^4 is 81×81 =(80+1)^2, which can be easily worked out. Similarly, 6^4 is 36×36 = (40-4)^2 which also can be easily worked out.

[@mohammedkamal3365]

الله يعطيك الصحة : ذلك هو التفكير السليم .

[@RealQinnMalloryu4]

3^{0+0 ➖ }=3^1 (x ➖ 3x+1).

[@drisslahlou2726]

900^4-600^4=( 900^4÷600^4-600^4÷600^4=(900/600)^4-1

[@MDSHAHIDULLAH-ze6xr]

the math is very easy

[@遠傳五華]

Factor 100 out first will save you a lot of troubles.