Q. Use Pascal's Triangle to expand (3z−3y)5. Express your answer in simplest form.Answer:
Identify Row for Exponent 5: Identify the row of Pascal's Triangle that corresponds to the exponent 5. The 6th row (since we start counting from the 0th row for the exponent 0) of Pascal's Triangle is 1,5,10,10,5,1. These numbers will be the coefficients in the expanded form.
Write Expansion Using Binomial Theorem: Write out the terms of the expansion using the binomial theorem and the coefficients from Pascal's Triangle.The binomial theorem states that (a+b)n=Σ((kn))⋅a(n−k)⋅bk, where Σ denotes the sum over k from 0 to n. For (3z−3y)5, a=3z and b=−3y, so the expansion will be:1⋅(3z)5⋅(−3y)0+5⋅(3z)4⋅(−3y)1+10⋅(3z)3⋅(−3y)2+10⋅(3z)2⋅(−3y)3+5⋅(3z)1⋅(−3y)4+1⋅(3z)0⋅(−3y)5
Simplify Each Term: Simplify each term in the expansion.Now we simplify each term by calculating the powers and multiplying the coefficients:1×(243z5)(1)+5×(81z4)(−3y)+10×(27z3)(9y2)+10×(9z2)(−27y3)+5×(3z)(81y4)+1×(1)(−243y5)This simplifies to:243z5−1215z4y+2430z3y2−2430z2y3+1215zy4−243y5
Check for Simplification: Check for any possible simplification or combination of like terms. There are no like terms to combine, and each term is already simplified.
Write Final Answer: Write the final answer in standard polynomial form, ordering the terms from highest degree to lowest degree.The final expanded form of (3z−3y)5 is:243z5−1215z4y+2430z3y2−2430z2y3+1215zy4−243y5
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